If you can't enter Safe Mode try this and then you can run chkdsk /r to check your disk and file structure.
Try Booting to the Recovery Console.
Boot the system using the Windows XP CD-ROM. In the first screen when the Setup begins, read the instructions press "R" (in the first screen) enter the Recovery Console.
1: C:\WINDOWS
Which Windows Installation would you like to log on to (To cancel, press ENTER)?
After you enter the number for the appropriate Windows installation, Windows will then prompt you to enter the Administrator account password.
Note If you use an incorrect password three times, the Windows Recovery Console closes. Also, if the Security Accounts Manager (SAM) database is missing or damaged, you cannot use the Windows Recovery Console because you cannot have correct authentication. After you enter your password and the Windows Recovery Console starts, type exit to restart the computer.
At the command prompt type:
chkdsk /r and press Enter.
Then try the System Restore to see if it will work for you.
Boot the system using the Windows XP CD-ROM. In the first screen when the Setup begins, read the instructions press "R" (in the first screen) enter the Recovery Console.
1: C:\WINDOWS
Which Windows Installation would you like to log on to (To cancel, press ENTER)?
After you enter the number for the appropriate Windows installation, Windows will then prompt you to enter the Administrator account password.
Note If you use an incorrect password three times, the Windows Recovery Console closes. Also, if the Security Accounts Manager (SAM) database is missing or damaged, you cannot use the Windows Recovery Console because you cannot have correct authentication. After you enter your password and the Windows Recovery Console starts, type exit to restart the computer.
Type the following command and press Enter.
Type CD\ then Enter
Then type cd system~1\_resto~1 then Enter
Type dir then Enter
When you hit enter it will list all the restore points folders like rp1, rp2 ??.. If the restore points have more than one page then you will have to keep on hitting the key to view the last restore point folder. You will have to choose the second to last option folder
Type cd rp {the second to the last restore point no. } (Note: Example: cd rp9, if rp9 is the second to the last restore point where the last restore point no. is 10
Then type cd snapshot
Now the command prompt will look like this c:\system~1\_resto~1\rp9\snapshot
Type: copy _registry_machine_system c:\windows\system32\config\system
Press enter
Then type: copy _registry_machine_software c:\windows\system32\config\software
Then type exit
TIP!.
If you get an access denied error when doing the above, then do the following at the recovery console:
Type CD\ then press Enter
Type cd windows\system32\config then press Enter
Type ren system system.bak then press Enter
Type exit and press Enter
Your PC will reboot, go back into the Recovery Console and then you have access.
Keep us informed as to your progress if you require further assistance.
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