How to recover a corrupted registry in Microsoft® Windows® XP?

When you try to start or restart Windows XP, you may receive one of the following error messages:

Windows XP could not start because the following file is missing or corrupt:\WINDOWS\SYSTEM32\CONFIG\SYSTEM

Windows XP could not start because the following file is missing or corrupt:\WINDOWS\SYSTEM32\CONFIG\SOFTWARES

Stop: c0000218 {Registry File Failure} The registry cannot load the hive(file): \SystemRoot\System32\Config\SOFTWARE or its log or alternate

Boot from the Microsoft® Windows® XP cd,

At the Press any key to boot from CD prompt, perform the following steps:

Press the .
The Windows Setup screen appears, and several files are loaded.
Press the key.
If prompted, select the number corresponding to the Windows installation you want to log on to (usually C:\WINDOWS).
Press the key.
Enter the Administrator password (if any) and press the key.
The C:\WINDOWS> prompt appears.

NOTE: If the system fails to boot, the following method of recovery is not possible.

To copy the restore point in the recovery console, perform the following steps:

Type cd \ and press the key.
Type cd system~1\_resto~1 and press the key.

NOTE: If a message Access Denied is displayed while attempting this fix, perform the following steps:

Type cd \ and press the key. Type cd windows\system32\config and press the key. Type ren system system.bak and press the key. Type exit and press the key. Restart the computer. Continue troubleshooting below.

Type dir and press the key
.A list of restore points appear. Choose the restore point which is dated the day prior to the occurence of the reported error.
Type cd rpx (where x represents the restore point you chose in the step above) and press .
Type cd snapshot and press the key. Type dir and press .
Type copy _registry_machine_system c:\windows\system32\config\system and press .
Overwrite system? (Yes/No/All): appears.
Type Y and press the key.
Type copy _registry_machine_software c:\windows\system32\config\software and press the key.
Overwrite software? (Yes/No/All): appears.
Type Y and press the key.
Type copy _registry_machine_sam c:\windows\system32\config\sam and press the key.Overwrite sam? (Yes/No/All): appears.
Type Y and press the key.
Type copy _registry_machine_security c:\windows\system32\config\security and press the key.
Overwrite security? (Yes/No/All): appears.
Type Y and press .
Type copy _registry_user_.default c:\windows\system32\config\default and press the key.
Overwrite default? (Yes/No/All): appears.
Type Y and press the key.
Type exit and press to restart the computer and remove the Windows CD.NOTE: If any error message is returned while in the recovery console, use an earlier restore point.

Method 2:Run the CHKDSK /R command in the Microsoft® Windows® XP operating system.
Insert the Windows XP CD into the CD drive.

Boot the system from the CD drive.

The prompt Press any key to boot from CD... appears.

Press the spacebar.

The Welcome to Setup dialog box appears.

Press the key to repair Windows by using the Recovery Console.

Select the number that is associated with the Windows installation you want to log into, and then type the administrator password (or press the key if no administrator password exists).

From Recovery Console, type the following command:

CHKDSK /R Press the key.

From the Recovery Console, type the following command:

EXIT Press the key to restart your computer.

NOTE: If the system still does not boot to the hard drive, attempt to run the CHKDSK /R command again. Depending on the corruption on the hard drive, it may take several tries to achieve a complete repair.