Windows XP SP1 Network Problem Solver

Mon, 2007-07-16 13:53 by admin · Forum/category:

Table of contents

Read this first

If Service Pack 2 or later/higher is installed, go to the Windows XP and 2003 Network Problem Solver.

However, if Service Pack 2 has just been installed and a problem has appeared immediately afterwards, you may want to read the document on Service Pack 2 problems first. You can find out which service pack is installed by right-clicking on My Computer, then selecting Properties. If a service pack is installed, it is displayed there, for example as, "Service Pack 2".

Consider upgrading all computers to Windows XP to avoid the more complex issues of mixed operating systems networks. Users without any networking experience should particularly consider this option. Try to avoid to network Windows XP with versions of Windows that are several generations older, particularly Windows 95, 98, and NT. It can be done, but it may cause a few tricky problems. If you still want to try to get the mixed network to function, please read on.

The next general step before any detailed troubleshooting is to update all involved computers to the latest service pack and patch status, using http://update.microsoft.com/, particularly any computers running older operating systems.

If you can install Service Pack 2 on the problem computers, then this article no longer applies, and you can use the Windows XP and 2003 Network Problem Solver instead.

A general advice, particularly after changing hardware, is to power everything down, including any routers, cable modems, switches, hubs, and the like, wait 10 seconds, then power them up again. Rebooting without powering down is not enough in some cases.

For a step by step guide to Windows XP Home Edition networking you can read a series of Microsoft Knowledge Base articles beginning with this one:

How to Set Up a Small Network with Windows XP Home Edition (PART 1)
http://support.microsoft.com/kb/813936/

For a 60 page tutorial that covers networking with several Windows versions please read File and Printer Sharing with Microsoft Windows and download the Word document FileSharing.doc. Tutorials and step by step guides are also available at www.practicallynetworked.com and in other places on the Web.

Also check the links at the end of this document.

So what do you do when you get error messages like, "\\XXX is not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions." or "Logon failure: the user has not been granted the requested logon type at this computer"? Unfortunately there is not a single cause, but a whole bunch of them. You have to check them one by one until you find your particular cause and put it right.

Please do not send email with support requests to me. Write such questions into this web page as comment or reply instead (click on Add new comment or reply below), or they should go to the newsgroup microsoft.public.windowsxp.network_web, where others and I will gladly try to answer them.

The following should help you to solve most of these common network problems.

Transport protocols

If you connect to the Internet through a cable modem or any other means that involves IP addresses that are not in the same subnet, please read Internet via Cable Modem first. Normally this does not apply to DSL (ADSL) or dial-up connections.

Of the three transport protocols NetBEUI, IPX (Netware, NWLink), and TCP/IP you need only one. Since the Internet uses TCP/IP, this article supposes that you have only this transport protocol installed. Having more than one transport protocol can cause various problems, such as slow browsing (please see the relevant chapter below), therefore it is not recommended, unless you have an overriding reason like IPX game playing or the abovementioned IPX connections between computers in different IP subnets due to unfavorable IP address allocation by cable Internet providers. Thus remove NetBEUI and IPX unless you are very sure that you need them.

Check your games first. Many also offer gaming over IP (for example using the UDP protocol), in which case only the TCP/IP transport protocol is needed. But some older games still require IPX. If you need IPX for local network game playing, remove all bindings to that protocol. You can do this as follows.

  • in Windows Explorer or on the desktop or in the start menu, right-click on: My Network Places
  • Click on: Properties
  • Click on the command: Advanced
  • Click on the command: Advanced settings
  • Use the tab: Network adapters and bindings
  • Remove the check marks from all occurrences of the IPX protocol.
  • Click on: OK

You could also use the IPX transport protocol for Windows networking and remove the checkbox from the TCP/IP protocol instead, but since everybody else uses TCP/IP, it is better to stick to that, in case you want to attach a guest's or friend's computer to your network and copy some files.

IP address 0.0.0.0

First of all, disable and re-enable the connection. When you change the IP address from automatic to a fixed IP address while the adapter is not connected, you always get a 0.0.0.0 address at first when the adapter reconnects. If this doesn't solve the problem, read on.

Symptoms:

  • You cannot obtain an IP address from the DHCP server. The IP address is 0.0.0.0.
  • The DHCP service is not running, although it is set to Start Automatic.
  • When you try to start the DHCP service, you get the error message: Could not start the DHCP Client Service on Local Computer. Error 1075: The dependency service does not exist or has been marked for deletion.

This problem can occur after uninstalling Norton AntiVirus, which sets the DHCP service as depending on itself. It can also occur when the computer name of the client computer is too long. Make sure that all computer names in your network are no longer than 15 characters.

First set a restore point, so you can undo your changes, should anything go wrong (Programs, Accessories, System programs, System restore).

After setting the restore point, to remove this dependency, do this:

  • Click: Start
  • Click: Run...
  • Type: regedit
  • Click: OK
  • Navigate to the following keys in the registry: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\DHCP HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NetBT
  • For each of these, on the right side, double-click: DependOnService
  • Delete any lines containing either SYMTDI or NISDRV.
  • Click: OK
  • Close the Registry Editor.
  • Reboot.

IP address 169.254...

If the computer cannot obtain an IP address from a DHCP (Dynamic Host Configuration Protocol) server, like a router using NAT (Network Address Translation), Windows will automatically assign an APIPA (Automatic Private IP Address) in the range:

Class B: 169.254.0.0 - 169.254.255.255 (Subnet mask: 255.255.0.0)

One likely cause is Winsock corruption, caused by adware or a virus. Please read the following chapter.

Winsock corruption

Winsock corruption can be caused by some software installation or, more likely, deinstallation going wrong or by advertising malware. Possible symptoms are:

  • The computer can apparently establish an Internet connection, but then you receive no data or cannot send data.
  • The computer cannot obtain an IP address from the DHCP (Dynamic Host Configuration Protocol) server and Windows therefore assigns an APIPA (Automatic Private IP Address) like 169.254....

Typical error messages are:

  • An operation was attempted on something that is not a socket
  • The page cannot be displayed
  • Initialization function INITHELPERDLL in IPMONTR.DLL failed to start with error code 10107
  • The operation failed since no adapter is in the state permissible for this operation.
  • The attempted operation is not supported for the type of object referenced.
  • Error 720: No PPP Control Protocols Configured

Another possibility is that, in Device Manager, when you click Show Hidden Devices, the TCP/IP Protocol Driver is listed as disabled under Non-Plug and Play drivers, and you receive error code 24.

Service Pack 2 adds a new command to repair the Winsock corruption problem.

netsh winsock reset

Using this command should normally not do any harm, so if you have unsolvable connection problems or spurious disconnections, try it. It does remove all nonstandard LSP (Layered Service Provider) entries from the Winsock catalog, which are usually adware or spyware entries, but if you happened to have a legitimate one installed, for example one that provides a PDA synchronization service, it would also be removed and would have to be reinstalled.

If you're really curious, you can use the command:

netsh winsock show catalog

before and after resetting the catalog to find out whether any entries were in fact removed and which ones these were. Another way to get at the same information is to run

winmsd

and select Components, Network, Protocol. The Layered Service Providers in the list should be of the MSAFD or RSVP ... Service Provider type. All others are likely malevolent and should disappear after the reset command shown above.

If you don't have Service Pack 2 installed, you can repair your software installation as described in the following Microsoft Knowledge Base articles.

How to determine and recover from Winsock2 corruption
http://support.microsoft.com/kb/811259/

You receive an "An operation was attempted on something that is not a socket" error message when you try to connect to a network
http://support.microsoft.com/kb/817571/

A third party product that can also solve this problem quickly is WinSockXP Fix, available at http://www.spychecker.com/program/winsockxpfix.html. One user reported that it solved his problem after all the other methods failed.

Some excerpts from selected emails:

After 4 hours of bothering, used the two "netsh" commands you suggested, to reset both winsock and tcp-ip. Both commands executed fine. Rebooted, tried the connection again, and all was fine. Took no longer then 5 minutes, this fix. I find your site highly informative, right to the point and much easier to read then microsoft's site. Keep this up! Very good work.

TCP/IP not working

To check whether TCP/IP is installed and working properly, find the IP address of each of your computers and, if present, of your router, then ping each computer from at least one other computer. You can find the IP address of each computer by going to that computer and running ipconfig (on Windows XP, 2000, NT) or winipcfg (on Windows ME, 98). Then ping your local computer through the localhost address by entering one of the following commands into a command line window and pressing return:

ping localhost ping 127.0.0.1

If this works, ping other computers by entering ping, followed by a space and the IP address of the target computer, then press return.

If the ping test fails, the low level connection between your computers (or, if ping localhost fails, even inside your computer) is not working, and there is no need to read on until this is repaired. The most radical method to repair it (short of reinstalling Windows) is to remove all networking components, reboot, then add them again.

One action you can try first is to repair the connection. Right-click on the connection (in the network connections list) and select Repair.

There is also the command:

netsh int ip reset

or:

netsh int ip reset log_file_name

where log_file_name should be replaced with a text file name of your choice.

Command samples:

netsh int ip reset resetlog.txt

netsh int ip reset c:\resetlog.txt

It is unclear whether this command does more, apart from the possible logging, than the Repair command described above, but if there is any difference, then the netsh int ip reset command is probably more thorough. Please add a comment or reply below if you ever find that the latter does or does not more than the former.

The appropriate Microsoft Knowledge Base article provides more details on this:

How to reset Internet Protocol (TCP/IP) in Windows XP
http://support.microsoft.com/kb/299357/

How to reset "Internet Protocol (TCP/IP)" in Windows Server 2003
http://support.microsoft.com/kb/317518/

XP Networking Wizard problems

Avoid running the wizard if you want to keep your network as it is and only want to integrate a new XP computer into it. Run it only if you accept that your network settings are restructured to conform to XP's ways.

If you have already run the wizard, just read on. This text will help you to undo the unwanted actions of the wizard.

If the wizard will not run, you can either try to repair the Windows installation or you can do without the wizard.

XP's built-in Firewall blocks Intranet/LAN connections

If you have service pack 2 installed, you have to activate a firewall exception, either one for File and Printer Sharing for the local subnet or a general one for your LAN connection. For more information, please see the firewall chapter in Windows XP Service Pack 2 Problems.

If you don't have SP2 installed yet, you can disable the XP firewall on a certain connection. Select Start, Settings, Network and Dial-up Connections, right-click on the desired connection (usually your LAN/Intranet), select Properties, Advanced, and deselect the firewall.

A third party firewall or other third party software, like antivirus software scanning the network, interferes

Zone Alarm, Tiny Personal Firewall, AtGuard, PC-cillin, and Kaspersky are examples. For example, Microsoft cites Kaspersky Labs Antiviral Toolkit Pro AVP in the Knowledge Base article:

You May Be Unable to Browse the Network
http://support.microsoft.com/kb/294756/

Uninstall third party firewalls and other questionable software, particularly antivirus software, entirely until you have your network working properly. Some firewall software (like Zone Alarm and AtGuard) is known to inhibit the network even if disabled.

If you want to keep using Zone Alarm, you can still do so if you use a sufficiently new version and set it up properly, for example with medium Internet Zone security and low Trusted Zone security and making sure your LAN address range is within the Trusted Zone. You can achieve that easily by defining an IP address range that contains all your LAN addresses (including router, if any), giving it a name, and putting that into the Trusted Zone. But it's safest to uninstall it first for a test.

Do not try to use two software firewalls in the same computer at the same time.

Workgroup is not accessible

If you get one of these symptoms or error messages or a similar one:

  • You cannot access shares on other computers.
  • You cannot locate other computers in the workgroup.
  • When you double-click the workgroup in My Network Places, you get the error message: Workgroup is not accessible. You may not have permission to use this network resource.
  • Workgroup is not accessible. The list of servers for this workgroup is not currently available.

Perform the following procedures, which could perhaps cause this problem, and read also the chapter below, "Network path not found". Retest after each procedure. Reboot after making nontrivial changes.

  1. If you have Service Pack 2 or higher installed, make sure the File and Printer Sharing exception is enabled in the firewall. Reboot to allow the browser service to start or start it manually (see below). Also see the Windows XP and 2003 Network Problem Solver or Troubleshooting Windows XP Service Pack 2, chapter Networking problems after installing Service Pack 2.
  2. Check whether the NetBIOS node type is P-t-P and you have no WINS server. Open a command line window and enter the command: ipconfig /all . Look for the NetBIOS node type, which may be Hybrid, Unknown, Mixed, or P-t-P. (P-t-P can mean Peer-to-Peer or Point-to-Point, but the given interpretation may be wrong.) If so, read the next chapter below: Network path not found.
  3. Make sure the Computer Browser service is running. To have the Computer Browser start automatically, select Administrative tools, Services, and change the Start setting for Computer Browsing to Automatic. You can then reboot the computer or start the service manually by clicking on the Start button. If this doesn't get the browser service to start, check all of its dependencies and make sure that all services on which the browser service depends are also running. For more details see http://support.microsoft.com/kb/318030/.
  4. Make sure you have only one transport protocol installed, namely TCP/IP. Remove, disable, or at least unbind (remove all bindings from) other transport protocols like IPX (NWLink) and NetBEUI.
  5. Check whether NetBIOS over TCP/IP is enabled. It should be for most networks. After you have solved the problem and if you have only Windows XP and 2000 or newer operatings systems in the network, you can try disabling it again to check whether it is not actually needed.
  6. Uninstall third party client software that can interfere with the networking settings. Such software could have come with network adapters or with a router.
  7. If you had other networking clients installed, like certain Netware clients, you may be in for a long, bumpy ride. Some do damage that is almost impossible to repair. You may want to try a repair installation of Windows XP, followed by applying Service Pack 2 again, or, better, a repair installation with a slipstream version of Windows XP with Service Pack 2 already integrated. See General above for details.
  8. Repair the IP stack with the Repair command or with the command: netsh int ip reset
  9. Repair the Winsock with the command: netsh winsock reset (Warning: This removes all third party Layered Service Providers—LSPs. Please see the subchapter on Winsock corruption above.)
  10. If the loopback feature is enabled in a connected router, disable it. You may even need a firmware upgrade.
  11. Change the workgroup name in all computers to a new, simple, short, perhaps even all upper case one, to make sure there aren't any problems there. You can later change it back.
  12. Check all NetBIOS names for possible duplicates. For example, if the workgroup name coincides with a user or computer name, this could cause the problem. Try opening a command line window and issuing the command: net view
  13. Issue the command: net view \\computername, where computername should be replaced with one of the names displayed with the simple net view command. Check all names for possible duplication.
  14. Check your router's diagnostic and information pages for NAT information, like which computer has which IP address. Any duplication here could point to the problem.
  15. Disable, better uninstall or upgrade, all antivirus software and third party firewalls.
  16. Rid the computer of adware and spyware. For example, run Spybot Search & Destroy.
  17. If all this doesn't help, remove all networking components, reboot, then set them up again and work through this checklist once more.

Two of these points are also explained in the following Microsoft Knowledge Base article.

You cannot access shared files and folders or browse computers in the workgroup
http://support.microsoft.com/kb/318030/

And, most importantly, if you find that one of these points or any other procedure solved your problem please add a comment or reply below and let me know!

Network path not found

This error message can occur if computers other than Windows 2000, XP, or later, are in the network, if there is no local DNS server, and if NetBIOS over IP is disabled. This constellation can cause the error message: Network path not found. It can also lead to the function "Show workgroup computers" not showing all (or any) computers.

To enable NetBIOS over TCP/IP, which you need to find pre-Windows-2000 (i.e. Windows 9x, ME, or NT) computers on the network, in Windows Explorer or on the desktop or in the start menu right-click on My Network Places, select Properties, select your network connection, right-click again and select Properties. Highlight the TCP/IP protocol and click on the Properties button, click on the Advanced button, then the WINS tab to get to the NetBIOS setting option. Select "Enable NetBIOS over TCP/IP" and wait a few minutes to let the machine rescan the network. You can also try the standard setting, which should normally suffice.

This issue may also occur if the TCP/IP NetBIOS Helper Service is not running on the client computer. To start this Service, go to Control Panel, Administration, Services, and double-click the TCP/IP NetBIOS Helper Service.

Another related and surprisingly frequent problem is the setting of an unsuitable node type for Windows networks (which use NetBIOS). First check your node type by opening a command line window and typing the command

ipconfig /all

This command reports the node type, among other information. It should be Hybrid or Unknown, but not Point-to-Point (p-node, actually a mistaken interpretation of Peer-to-Peer), because that would work only when a WINS server is present.

If the node type is P, you can use regedit.exe to go to

HKEY_LOCAL_MACHINE
 \System
  \CurrentControlSet
   \Services
    \Netbt
     \Parameters

and delete any of the two values NodeType and DhcpNodeType if they exist, forcing Windows to fall back to its default node type, which should be Hybrid. Reboot.

More details can be found in the article "Default Node Type for Microsoft Clients" at http://support.microsoft.com/kb/160177/.

2005-03-22 - Doug Latornell writes that he observed that the Intel Netstructure VPN client changed this setting and didn't change it back when uninstalled. Thanks, Doug!

Access methods, access rights, or passwords not properly set

Simple and classic file sharing

In Windows XP Professional, if you desire classic file sharing based on username and password instead of XP's default method of allowing only Guest access, go to Start, Control Panel, Folder Options, View, and uncheck "Use Simple File Sharing (Recommended)". Click on OK.

Note that this is not generally required for file sharing. Simple File Sharing should work fine, but Classic File Sharing allows you to assign different access rights to different user accounts.

Conversely, if you want to access other computers from XP using the classic method instead of Guest access, go to the same place and check "Use Simple File Sharing (Recommended)" again.

Alternatively you can use Control Panel, Computer administration, Group policies, navigate to Security Settings, Local Policies, Security Options, and find the policy named "Network access: Sharing and security model for local accounts" and set that to "Classic - local users authenticate as themselves".

After such a fundamental change, particularly when changing from Classic to Simple File Sharing, it may be necessary to remove and re-establish the sharing for all shares, one by one, in Windows Explorer to make sure the shares are accessible by Guest. Be sure to remove the sharing and close the dialog completely by clicking on OK, then open it again and re-establish the share.

Wrong username

One particularly insidious mistake is to change the user name in User Manager, believing that that is the actual username used for authentication, which it isn't. To find out for sure, use Control Panel, Computer Management, Local Users and Groups, Users. There you can change the actual username, by pressing F2 or by clicking on it, waiting a second, then clicking on it again.

Password

To set or change the password in Windows XP, select Control Panel, Administrative Tools, System Tools, Local Users and Groups, Users. Right-click on a user name to set password. You also have to set permissions for all users on the shared objects (folders, files, printers, etc.). Usually this is done through groups, which contain the users. Later use this same user name and password to log on from other computers.

Permissions, access rights

Make sure that the share access rights are sufficient (i.e. if the access is through the Guest account, make sure Guest or the group Guests has the desired access. Then do the same for the access rights to the folders and files in the share. Remember, you have to check access rights twice—once for folders and files and once for the share. The latter are set on the share tab; look for the button there. If you have set the object permissions properly, you can simply set the share permissions to Everyone, Full access.

Manage my network passwords

When you get an error that you have no permission to access a share, another possible cause is that Windows XP is using a saved, but obsolete password. To remedy this, use Control Panel, User Accounts, click on your own account, select "Manage my network passwords". Check whether the problem computer shows up in the list. If it does, click on it and select Remove.

Slow browsing because of wrong network passwords

Slow browsing of Windows ME, 98 or earlier versions can also be caused by inappropriate network passwords. Use Control Panel, User Accounts, click on your own account and select "Manage my network passwords". If you have any user name preceded with the computer name of an ME or 9x computer, change it to contain the XP computer name and the account name you use on the XP machine, but add the share password you have set on the ME or 9x computer, if any. If there are no passwords set on any ME or 9x shares or printers, then you may be able to make it work by deleting such entries in the "Manage my network passwords" list altogether.

Space in Windows 9x or ME computer name

Accessing password-protected shares on Windows 9x or ME computers from a Windows XP computer does not work when the computer name of the target computer contains a space. The XP computer shows the password prompt and uses Guest as the username, which is greyed out and cannot be changed. Change the computer name on the Windows 9x or ME computer to one without any spaces.

Windows XP Home Edition has simple file sharing only

Windows XP Home cannot accept network accesses with user name and password and can only be accessed with Guest credentials (simple file sharing, see below). The Guest account may have to be enabled for that. Note that disabling the Guest account in the control panel, through User accounts, does not actually disable the Guest account, but only disables local console logon to it and leaves the Guest account active and open for network logons, because this is needed for simple file sharing.

Autologon in Windows XP Home Edition

Windows XP Home uses autologon as the default. The first logon is done as owner without a password. When you then set up a user account and log on, you do not get the user prompt because autologon is active. However, you are not logged on as the new user, but still as the owner, so you may not be authenticated as expected by other computers. To resolve this, use Control Panel, Users and disable autologon, then log off and on again as the desired user. After this you can re-enable autologon, if you like.

How to log on to Windows 9x or ME

On non-XP versions of Windows like 95, 98 and ME the simple Windows Logon often works better than the Client for Microsoft Networks when the only problem is to connect to an XP computer. What definitely doesn't work is no logon at all. If you don't even see the logon dialog box, then log off and log on again first.

Automatically changed passwords

Windows 2000 and probably also XP can, and sometimes does, for no good reason, change or disable passwords on other computers (seen on Windows 2000). Moreover, Windows XP sometimes alters or disables the Lan Manager password, so computers with Windows 9x or ME suddenly get authentication failures (wrong username or password errors, 0xC000006A in the security log) and subsequent account lockouts (0xC0000234 in the security log). If you have such inexplicable authentication problems, go to the Windows XP or 2000 computer you are trying to access, re-enter the password and re-enable the account if it's still locked out. Extending the password validity time to 999 days instead of 0 does not help—it still stops working after something like 42 days for Lan Manager passwords. This problem seems to occur only when a Windows 9x or possibly ME computer tries to access a Windows XP or 2000 computer.

Simple file sharing, Guest account, and anonymous access problems

Background: Simple file sharing, the only method on Windows XP Home and one of two choices on Windows XP Professional, always uses the Guest account. (Classic file sharing also automatically uses the Guest account if the original logon request fails.) If access through the Guest account is inhibited, then sharing cannot work, except by logging on to XP Professional with classic file sharing through another account.

There is a user rights policy to deny network access to certain users and groups, which contains a SUPPORT user and, by default, Guest. If Guest is included here, guest and anonymous access (all users who do not have an account with the same username and password on the target computer) from other computers is not possible and yields the error message, "Logon failure: The user has not been granted the required logon type at this computer.". Double-click on the policy and remove Guest from it if you want to allow anonymous access.

Windows NT and 2000 automatically treat failed attempts to log on over the network in a second attempt to log them on anonymously, i.e. as Guest. Windows XP can do this too, but it has to be enabled first, particularly on XP Professional.

To make sure Windows XP Home is set up properly, you can run the Network Setup Wizard. If you use a router, select the option where the computer connects to the Internet through a residential gateway. The Guest account should have no password. If you are not sure whether this has mistakenly been changed, you can remove any password from the Guest account with the following procedure.

  1. Click on: Start
  2. Click on: Run...
  3. Type into the data entry field: control userpasswords2
  4. Click on: OK
  5. Click once on: Guest
  6. Click on: Reset Password
  7. Do not enter any password, leave the two fields empty.
  8. Click on: OK

For network access to Windows XP Pro with classic file sharing (Simple File Sharing disabled) through the Guest account, the Guest account has to be enabled on Windows XP and network login for the Guest account has to be permitted in Computer Management, Local Users and Groups. The same is needed for Simple File Sharing in XP Pro and XP Home if the Guest account had been disabled. A quick way to enable Guest network access is to type the following command at a command prompt:

net user guest /active:yes

If this doesn't solve the problem and you are still being asked for a password, check for stored network passwords.

  1. Click on: Control Panel
  2. Click on: User accounts
  3. Click on your own account.
  4. Click on: Manage my network passwords
  5. Check whether there are any stored passwords for the target computer. If so, remove them.

If, however, the problem is just the other way around and you actually want to see the "Connect as" dialog, you have to disable the Guest account on the target computer, i.e. the server, the computer on which the objects are that you want to access.

Note also that the settings in the user manager in the control panel have nothing to do with networking. Disabling the Guest account there only has the effect that nobody can log on locally (at the keyboard). It does not have any effect on network access.

On an NTFS partition, Windows XP Home does not allow to share these folders:

  • User folders directly in Documents and Settings
  • Program Files
  • The main Windows folder

It is possible, however, to share subfolders within those folders.

Trying to log on to XP Professional with an empty password

If you try to log on to Windows XP Professional with classic file sharing (Simple File Sharing disabled), without password (i.e. with a totally empty password), you normally get an unknown error 31. To be able to use empty passwords, for example as Guest, use the group policy editor to disable the option, "Limit local account use of blank passwords to console login only". To get there, use Control Panel, Performance and Maintenance, Administrative Tools, Local Security Policy (or click Start, Run, type gpedit.msc and click OK), expand Local Policies, Security, double-click Accounts: Limit local account use of blank passwords to console login only, which is enabled by default. Disable this option.

For simple file sharing (i.e. always in Windows XP Home) this does not apply. Also, the Guest account does not normally have a password and does not need one.

Machines mistakenly set for domain access

When no domain controller is present, computers must not be set for domain access. For example, in Windows 98 make sure that the client for Microsoft networks does not contain a domain name.

Outlook Express cannot find network

Open Internet Explorer and select Tools, Internet Options, Connections. Click on the LAN Settings button. Clear the check box for Automatically detect network settings. In Outlook Express check whether the similar setting in Tools, Options, Connections, Change button, LAN Settings button, is also cleared. It should be.

Please add a comment or reply below and let everybody know the precise error message if you had this problem and could correct it by following this procedure.

Cannot browse some web sites

If you use the PPPoE protocol (or some other Internet link protocol that requires extra header space), for example for a DSL connection using a router or ICS (Internet Connection Sharing), you may have to reduce the MTU (Maximum Transmission Unit) on the client computers from the default of 1500 to 1492 (or in certain circumstances even less), because the PPPoE protocol takes 8 bytes away for an extra header. Some other protocols and routers also require a reduced MTU, sometimes even much less than 1492 bytes.

First of all, check your router and make sure it doesn't have a needlessly low MTU setting. If your router has such a setting, try to increase it as far as possible.

If that doesn't solve the problem, and even if it does, install Service Pack 2 at least on the ICS host computer, which should, in theory, fix the problem. (Actually it was already fixed in Service Pack 1.) However, there seem to be cases in which the problem persists even after Service Pack 2 has been installed. In that case, please read on.

An elegant way to solve it is to uninstall your current PPPoE driver and install RASPPPoE instead, a free, but excellent driver you can download from http://user.cs.tu-berlin.de/~normanb/. This driver has excellent automatic MTU discovery.

Another way is to change the settings on all computers, including all clients. You can do that with the help of a small freeware program named DrTCP, which you can download from http://www.dslreports.com/drtcp, a site that also contains quite a few good explanations of the background for all this, including explanations on how to do all this by hand.

You can check your TCP/IP settings by going to the web site http://www.speedguide.net/ and look for Broadband Tools. They also have a program similar to DrTCP, but their program is (as of 2004) quirky and poorly designed.

If there are any doubts, reduce the MTU setting to 500 bytes for a test. This is a value that should always work. If even this doesn't resolve the problem, set it back to 1500. Your problem is not related to MTU. If this does resolve the problem, try to find the largest MTU value that works for you, usually in the range between 1440 and 1492 bytes.

For more details you can read the following Microsoft Knowledge Base article.

Connectivity Problems on ICS Clients When You Use a PPPoE Connection on a Windows XP ICS Host
http://support.microsoft.com/kb/319661/

Shared folder name does not appear on mapped network drive in Windows Explorer

In Windows Explorer you can see a mapped network drive, but its folders are not displayed on the right side. Possible error messages are:

  • Read Access Withdrawn (RAW)
  • The file system on the server does not support long file names.

The following Microsoft Knowledge Base describes this defect and the workaround.

Shared Folder Name Does Not Appear on Mapped Network Drive in Windows Explorer
http://support.microsoft.com/kb/817861/

Computer and share name limitations

Remove spaces. In particular, change the computer names on older operating systems that allow spaces in computer names.

Share names on newer operating systems should not be longer than 12 characters to be recognized by Windows 9x or ME.

Inappropriate DNS or WINS settings

Make sure you do not have any wrong settings in the DNS or WINS setup. In a small peer-to-peer network no such settings are needed. If you run a server with Active Directory, you need DNS though, but this makes little sense in a small network.

Lower case characters in passwords for connections from Windows 9x or ME computers

Under certain infrequent circumstances XP appears not to accept passwords from Windows 9x or ME if they contain lower case characters. If you cannot determine and remove the cause, you can, first as a test, then as a crutch, circumvent this by setting the passwords to all uppercase (or, for example, numbers only).

If this actually solves your problem, try now to enter yet another password containing lower case characters. It is possible that the act of changing the password solved your problem, not the upper case characters. If the error then reappears, you can still change it back to all upper case again.

Adapters are set to full duplex, although the connection is to a hub or other device that cannot perform full duplex

This sometimes leads to a functioning network, but to very poor performance due to a large number of Ethernet collisions. Please check your switch for collision indications while copying a large file through it.

Try to force the adapter driver to use half duplex.

Shares on Windows ME or 9x computers are not reconnected after booting

When you have shares on Windows ME or 9x computers that are protected by different passwords, Windows XP only reconnects to one share at best, but the others are not automatically reconnected after booting. Possible solutions:

  • Try to give all shares the same password.
  • Reconnect them by hand.
  • Write a batch file that is run at logon time and that reconnects the shares.

See the following Microsoft Knowledge Base article for details.

Share-level mapped network drives are not connected after you restart your computer
http://support.microsoft.com/kb/283492/

Cannot access Windows ME or 9x computer because no share is defined on it

Should be obvious, but is sometimes forgotten.

Computer Browser slow

Consider that in a simple local network it can take up to 15 minutes until all computers show up in Explorer or My Network Places. In a complex, routed network it can take more than an hour. So be patient or connect a network drive using the Tools command in Windows Explorer.

To find out the browser situation in your LAN, you can use the BROWSTAT.EXE program. This little (40 KB) tool from Microsoft can show which computers are browsers. More information is here:

Troubleshooting the Microsoft Computer Browser Service
http://support.microsoft.com/kb/188305/
You can download Browstat from http://www.dynawell.com/reskit/microsoft/win2000/browstat.zip or http://rescomp.stanford.edu/staff/manual/rcc/tools/browstat.zip

Unzip it and copy BROWSTAT.EXE to a suitable folder, preferably one in the path. If you aren't sure about this, you can copy it into the main Windows folder.

To use it, open a command line window and first type

browstat

This yields a short explanation of the command. Then, to find out the transports, type:

browstat dn

This will show you the available transports on your computer. Memorize the number of the transport for your LAN. In the following command the number 1 is assumed, but it can be a different number, like 2 or 3, if you have more than one transport.

browstat vw 1

This command lists the computers in the workgroup and their functions. Yet another useful command is:

browstat status

This command yields information about the computer you are sitting at.

Slow browsing of pre-XP computers from XP due to inappropriate computer names or passwords in XP

In XP go to Manage Passwords and delete any computer names or passwords for pre-XP computers. The next time you try to log on, you will get a password dialog box. Enter the correct password for the share if there is any.

For more information on managing stored credentials see the following Microsoft Knowledge Base article.

HOW TO: Manage Stored User Names and Passwords on a Computer That Is Not in a Domain in Windows XP
http://support.microsoft.com/kb/306541/

Slow Windows XP computer, fast Non-XP machines

This can be caused by Windows XP dealing with scheduled tasks on the non-XP computers. To prevent this, do the following on the XP computer: Start the registry editor, for example by clicking on the Start button, selecting Run and entering:

regedit

Then press return.

Navigate to the following key.

HKEY_LOCAL_MACHINE
 \SOFTWARE
  \Microsoft
   \Windows
    \CurrentVersion
     \Explorer
      \Remote Computer
       \NameSpace
        \{D6277990-4C6A-11CF-8D87-00AA0060F5BF}

Disable it for a test by renaming it. For example, press [F2] (or right-click on it and select rename), then put the cursor before the first brace and enter DISABLED or, in fact, anything you like. They key could then be named, for example:

DISABLED {D6277990-4C6A-11CF-8D87-00AA0060F5BF}

Press return to enter the changed key name.

Close the registry editor and reboot the computer.

Now test the network. Is it much faster? If so, you're all set. If not, you can repeat the procedure and rename the key back to what it was to stay on the safe side.

Lose access to shares and printers after 3 minutes

If none of your network components uses the IEEE 802.1x authentication protocol, you may experience that network connections break after about three minutes. The symptoms are that you can still see the other computers, but you cannot access their shares or printers.

You can prevent these disconnects by disabling the protocol. A normal home network does not use this protocol.

In Windows XP before service pack 1, in Windows Explorer or on the desktop or in the start menu, right-click My Network Places, select Properties, right-click the LAN Connection, select Properties again, click the Authentication tab and uncheck "Enable network access control using IEEE 802.1x." Click on OK. In the unlikely case that you do have an IEEE 802.1X server on your network, this would lead to authentication failures, so you'd have to reenable the protocol.

In Windows XP with service pack 1 (or Windows Server 2003), for wireless adapters there is no longer an Authentication tab. Instead right-click on the connection's icon (either from system tray or from connections folder), select "View available networks", uncheck the "Enable IEEE 802.1x ..." checkbox and click Connect.

The same setting can also be found by selecting the connection's Properties, then select the Wireless networks tab, which is a part of the Properties dialog of each of the preferred networks (there are two tabs there, Association and Authentication). This is so because the state of 802.1x (enabled or disabled) is specific to each of the preferred networks.

Again, if this leads to authentication failures, then double-check whether you do need the protocol after all. If so, you have to reenable it.

DNS Client service running in a workgroup

In a workgroup (not domain), if networking works perfectly as long as you use IP addresses, but fails when you use host names, the cause may be that the DNS Client service is running. Stop and disable it permanently. It is only needed in Windows Server domains, not in workgroups, and it tends to get in the way.

Advanced tab missing in firewall - network bridge used unnecessarily

If the Network Bridge shows up in your network configuration, make sure that you really need it. If not, delete it, but if you use Internet Connection Sharing, disable it before you delete the Network Bridge and re-enable it afterwards.

If you cannot delete a network bridge, read the following Microsoft Knowledge Base article:

An Unexpected Error Occurred" Error Message When You Delete the Network Bridge
http://support.microsoft.com/kb/824922/

Cannot add WebDAV server to My Network Places

In the logon authentication dialog box try to add the NetBIOS name of the server in front of your username, separated by a backslash.

For more information please read the following Microsoft Knowledge Base article.

Cannot Add FQDN Web Folders that Require Basic Authentication to "My Network Places"
http://support.microsoft.com/kb/315621/

Faulty or obsolete drivers, drivers that are not fully compatible with Windows XP

Check and remove or replace. One reported example is that even the latest drivers provided by Microsoft for 3Com network adapters didn't solve a slow data transfer problem in the direction to XP, but the latest drivers from www.3com.com did.

VPN policy active

Disable the VPN (Virtual Private Network) policy that may have been set by Secure Remote software or similar.

Network cable unplugged

If you receive this message, but your cable is actually connected, suspect a loose connection, a failed cable, or an intermittent failure of the network adapter or the switch at the other end of the cable.

Spooler SubSystem App encountered a problem and needs to shut down

This problem is solved by Service Pack 2, so the recommendation is to install that or a higher service pack.

There is also a simple workaround. Open a command line window, then enter:

net stop spooler

Press return to enter the command. Now try to run the Network Setup Wizard again.

The spooler, which you need for printing, will automatically restart when you reboot the next time. If you need it now, enter the following command:

net start spooler

Public IP adresses

If you have public IP addresses (see Private IP Addresses for details), you need one of the following:

  • A set of well-working DNS servers, reachable over a fast connection, faster than modem
  • Your own DNS server on your subnet
  • A DNS proxy, which may be built into your Internet router (activate it)
  • HOSTS files on all local computers, pointing to all local computers. Don't forget to update these whenever any IP address changes.

You also need a well-working firewall, or you need to safeguard each computer carefully to be safe from hacking attacks.

Others

Some networking problems can be resolved by right-clicking on the connection and selecting Repair. Some more problems, particularly on Windows 9x and ME, are resolved by removing all networking components, rebooting, then adding and setting them up again. Always try this when the problem could be in one of these Windows versions.

Occasionally the WebClient service or the Background Intelligent Transfer Service gets in the way. Try to stop these services for a test. To stop the WebClient service for a test, right-click My Computer or select Start, Control Panel, System and select Manage, double-click Services and Applications, double-click Services, double-click on the WebClient service, click on the Stop button. If you want to disable it for good, change the startup type to Disabled. Finally click on OK.

On Windows 9x avoid the Microsoft Family Logon in the network components. Use the Client for Microsoft Networks instead.

If it still doesn't work, make sure your computer description is short, no longer than about 40 characters. XP doesn't always seem to see computers on the network when they have very long descriptions.

Occasionally a shortcut in My Network Places stops working. To resolve this, delete the offending shortcut, in Windows Explorer or on the desktop or in the start menu, right-click My Network Places, use Search for Computers, and drag a new shortcut into My Network Places.

Slow file copying over the network (reported between Windows XP and 2000) can sometimes be repaired by right-clicking on My Network Places in Windows Explorer or on the desktop or in the start menu, then selecting Properties, Advanced, Advanced Settings, Change the provider order. Just shift some services up or down, then click on OK and reboot. It is not yet known whether the order matters or whether just any arbitrary change somehow repairs the defect. Please add a comment or reply below to let everybody know if you happen to find out.

More relevant information, Knowledge Base articles etc.:

How to Set Up a Small Network with Windows XP Home Edition
http://support.microsoft.com/kb/813936/

How to configure file sharing in Windows XP
http://support.microsoft.com/kb/304040/

You May Be Unable to Browse the Network
http://support.microsoft.com/kb/294756/

Slow Performance Copying Files to Windows 2000 Domain Controller (Appears to affect any version of Windows NT, 2000, and XP.)
http://support.microsoft.com/kb/321098/

You Cannot Create a Network Connection After You Restore Windows XP
http://support.microsoft.com/kb/329441/

Documents in Word format:

Troubleshooting File and Printer Sharing in Microsoft® Windows® XP
http://www.microsoft.com/downloads/details.aspx?familyid=fd7fd48d-6b4a-448e-a632-076f98a351a2&displaylang=en

Troubleshooting Internet Connection Firewall on Microsoft® Windows® XP
http://www.microsoft.com/downloads/details.aspx?familyid=b3d01193-ad93-492f-b74b-97c2fc44e08b&displaylang=en

Troubleshooting Internet Connection Sharing on Microsoft® Windows® XP
http://download.microsoft.com/download/9/3/1/9315bee6-498e-493e-83a6-2a9d8631878d/ICS_Tshoot.doc

This message is not complete. There are various other potential causes for network problems.

If you could solve your problem, I'd be grateful for a comment or reply below, stating what did it.

Please do not send email with support requests to me. Such questions should always go into a comment or reply below or to the newsgroup microsoft.public.windowsxp.network_web, where others and I will gladly try to answer them.