Windows SP3 failed to install and now pc does not boot

If you can't enter Safe Mode try this.

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 u 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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First download the SP3 iso:
http://www.microsoft.com/downloads/details.aspx?familyid=2fcde6ce-b5fb-4488-8c50-fe22559d164e&displaylang=en
And burn this to disk using a ISO burner or:
http://www.ntfs.com/iso-burning.htm
When you have these disks ready then do a FULL re-install of Windows XP, download the SP2 and then whack on the Sp3 that you have burnt to disk, when finished you will need to go to the update page on the Microsoft web page and add on any updates available to you. This way your errors will become minimal.

Please post back if you have any more problems or questions.
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