Occasionally, it becomes necessary to replace a user's hard disk because of space limitations. One potential problem after you clone the old disk to a new one and try to logon is that the computer fails to log on and repeatedly displays the logon dialog box. You might also receive a message that the system has no paging file or that it is too small.

The likely cause of the problem is that the Globally Unique ID (GUID) of the new drive is different from the old one, and Windows has assigned a different drive letter to the boot volume.

There are a handful of ways to fix the problem, but the easiest is to boot the computer from a Windows 9x boot disk and use the FDISK /MBR command to recreate the master boot record, and then restart the system. (Make sure the boot volume is the only one in the system when you do this.)

Here are some other potential solutions:

* Open Registry Editor on another computer and open the problem system's registry from across the network. Change the value of

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\Current Version\Winlogon\Userinit:Reg_SZ:C:\WINNT\


HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\Current Version\Winlogon\Userinit:Reg_SZ:userinit.exe.

* If another volume in the computer has been assigned the drive letter of the previous boot volume, create the folder \Winnt\System32 on that volume and expand a copy of userinit.exe from the Windows CD to the folder.

After you are able to log on, follow the steps in the Microsoft Knowledge Base article 223188 to change the drive letter of the boot volume back to its original. (You can omit this step if you use the FDISK /MBR fix.)

NOTE: Editing the registry is risky, so make sure you have a verified backup before making any changes.