Method 1: Restore the SAM File from Backup
If you used the Backup utility in Windows XP to back up the system state, you can restore the SAM (and all other registry settings) from the disk or archived copy by using the Restore Wizard or the Automated System Recovery Wizard. 309340 (http://support.microsoft.com/kb/309340/EN-US/ ) HOW TO: Use Backup to Restore Files and Folders on Your Computer in Windows XP
Note ASR is not supported on Windows XP Home Edition.
For additional information about using the Backup utility in Windows XP, click the following article number to view the article in the Microsoft Knowledge Base:
Back to the topMethod 2: Copy the SAM File from the Repair Folder
If you cannot restore the SAM file by using the Windows Backup utility, copy the SAM file from the following location C:\WINDOWS\repair
and paste it to this location: C:\WINDOWS\system32\config
NoteBack to the topMethod 3: Reinstall Windows XP
When you do this, you will lose all accounts or groups that had been created. You will also need credentials that were valid at the time that the ASR was run. This will restore the SAM back to the last instance that Automated System Recovery (ASR) was run, or to when the system was first installed. To do this, follow these steps: Do either of the following:
Start the computer from another operating system (if you have a multiple-boot system).
If Windows XP is installed on an NTFS file system drive, you must start the computer from an operating system that can access the NTFS drive (for example, Microsoft Windows 2000 or Microsoft Windows NT). If Windows is installed on a FAT32 drive, you can start the computer by using Microsoft Windows Millennium Edition (Me) or Microsoft Windows 98.
Perform a parallel installation of Windows XP, and then start the computer from the parallel installation.
For additional information about how to perform a parallel installation of Windows XP , click the following article number to view the article in the Microsoft Knowledge Base:
) HOW TO: Install Windows XP
, click Run
, type cmd (or command if you are using Windows Me or Windows 9
, and then click OK
At the command prompt, type each of the following commands, pressing ENTER after each command:
copy c:\windows\system32\config\sam c:\windows\tmp\sam.bak
copy c:\windows\repair\sam c:\windows\system32\config\sam
This procedure assumes that you have Windows XP installed in the following default location:
Restart the computer by using the original installation of Windows XP.
If you cannot restore the SAM file by using either Method 1 or Method 2, you must reinstall Windows XP to replace the SAM file.
Note You must use the New Installation option to replace the SAM file. If you perform use the In-Place Upgrade (Reinstallation) option for Windows XP, the SAM file is not replaced. This method may require that you reformat the partition that Windows XP is installed to. Before you continue with this method, make sure that you have a backup of your My Documents folder, or select an option to install Windows XP to a different partition than where Windows is currently installed.