When you log on to Windows, or after you install Windows, you may receive the following error message, and your computer may stop responding (hang):

This behavior can occur for any of the following reasons:

• Your password list (.pwl) file is damaged.
• A service or program that loads during the startup process conflicts with another service or program.
• You are using user profiles.
• There is a hardware conflict on your computer.
• A hardware driver on your computer is missing or damaged.
• If profiles are enabled, Windows may not be able to contact the primary domain controller's Netlogon share when looking for a Config.pol file. (Windows checks for a Config.pol file even if policies are not used.)
• Your primary domain controller (PDC) is not local to your Windows 95 or Windows 98 clients.
• A single user profile is corrupted.
• Your network adapter is not correctly seated.
• You are using a reserved word for your user name.

To resolve this issue, use the following methods. After each method, test to see if the issue is resolved. If the issue continues to occur, use the next method.

Damaged Password List File

To re-create your password list file, use the following steps.

Note If you are using a personal certificate, you should export it before renaming your .pwl file. If you do not do so, it may be unavailable when you send e-mail messages. For more information, see the following article in the Microsoft Knowledge Base:

1. Click Start, point to Find, and then click Files Or Folders.
2. In the Named box, type *.pwl, and then click Find Now.
3. Right-click the Username.pwl file, and then click Rename, where Username is the name you use to log on to Windows.
4. Rename the Username.pwl file to Username.old, and then press ENTER.
5. Restart Windows.
6. When your computer restarts, you are prompted for a user name and password. If you want, you can choose to create a null password. If you create a null password, you are no longer prompted to log on when Windows starts. To create a null password, leave the password box blank, click OK, and then click OK to confirm the password.

Conflicting Service or Program

To prevent a conflict with a service or program, "clean" boot your computer. For additional information about clean booting, see the following articles in the Microsoft Knowledge Base:

User Profiles Are Being Used

To disable user profiles, follow these steps:

1. Right-click Network Neighborhood, and then click Properties.
2. On the Access Control tab, click Share-Level Access Control, and then click OK.
3. Restart your computer.

Hardware Conflicts

To resolve hardware conflicts, follow these steps:

1. Click Start, point to Settings, and then click Control Panel.
2. Double-click System, and then click the Device Manager tab.
3. Double-click any device that displays a yellow exclamation point or red X.
4. Click to select the Disable This Device check box, and then click OK. Repeat steps 3 and 4 for each device that contains a yellow exclamation point or red X.

Missing or Damaged Driver

Download the latest drivers for your hardware from your hardware manufacturer. For information about how to download the latest drivers for your hardware, view the documentation included with your hardware, or contact your hardware manufacturer.

Enable Load Balancing

To prevent Windows from contacting the primary domain controller, enable load balancing. For more information about enabling load balancing, click the following article number to view the article in the Microsoft Knowledge Base:

Remote PDC

Enable load balancing on the Windows clients. For additional information about enabling load balancing, click the article number below to view the article in the Microsoft Knowledge Base: Note Even if you do not use policies for your clients, Windows checks the PDC's Netlogon share for a policy file. If your PDC is not local to the client, or is across a slow wide area network (WAN) link, it could cause a long delay during the logon process.

Corrupted User Profile

Log on as a user who is not currently experiencing the issue. Locate the affected user's profile in the Windows\Profiles folder. Move that user's folder to another location. Log off and then log on as the affected user to re-create the user profile.

Incorrectly Seated Network Adapter

A network adapter that becomes inoperable or unseated can also cause this error message. Try to reseat, replace, or reinstall the network adapter.

Reserved Word Used as a User Name

The error message can also occur if you use one of the following reserved words as your user name:

• AUX
• CON
• COM1
• COM2
• COM3
• COM4
• PRN
• LPT1
• LPT2
• LPT3
• LPT4

Change your user name to something other than a reserved word.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

For additional information about Mprexe.exe issues, see the following articles in the Microsoft Knowledge Base: