So funktioniert es:   Solution:

1. manually create a restore point (just in case)
2. delete these keys from the registry:
   1. KEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows XP\SP3\KB940157
   2. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\KB940157
3. reinstall the standalone "exe".
4. now you can see the "$NtUninstallKB940157$" directory. Open this dir and look for a dir named "spuninst". Within the spuninst dir you should find a file named "spuninst.exe". Running this file should manually uninstall Windows Search.

Quelle: Link offline