Fix Windows XP SP3 Installation Problem

Problem :

Windows XP Service Pack 3 Setup Error:
Service pack 3 setup cannot update a checked (debug) system with a free (retail) version of Service pack 3, or vice versa.


Solution :

To reset the default security provider in Windows XP, delete the relevant registry keys in the Windows registry.

To do this, follow these steps:



1. Start the computer. Press the F8 key during startup to start the computer in Safe mode.
2. Start Registry Editor (Regedt32.exe) by using the Run box and enter regedt32.exe
3. Locate the below sections in the registry and delete only the Providers registry keys in the Windows registry:
HKEY_USERS\.DEFAULT\Software\Microsoft\Cryptography\Providers
HKEY_USERS\S-1-5-20\Software\Microsoft\Cryptography\Providers
4. Quit Registry Editor.
5. Restart the computer.

You must be certain to follow these instructions to the letter, since if you delete the wrong listing, the system might not boot. After the reboot, see if Windows XP SP3 will install.