her er kommando til at ret fejlen
When registration of the engine is corrupted, all attempts to run .msi packages fail.
To correct the registration of the Windows Installer, unregister and then register the Installer service using the command line switches shown below. This shuts down and reregisters the service, which assures that the Windows Installer engine should function properly. Enter the following commands from a command prompt:
msiexec /unregister
msiexec /regserver
If this fails to resolve your problem try performing the following steps:
1) Unregister Windows Installer:
msiexec /unregister
2) Rename the following files from the command prompt: Msi.dll, Msiexec.exe, and Msihnd.dll
3) Restart Windows.
4) Windows Installer installation program to perform a fresh installation.
Se også
http://support.microsoft.com/default.aspx?kbid=292539