Try these for size, one or both together should cure the problem.
- Start -> Programs -> Accessories -> right-click Command Prompt and select Run as Administrator)
- run the following command:
You may have to run to command more than one time, since it will need to stop the WMI service first. Repeat it until the message "WMI repository is consistent" appears.
Another option for Vista is the following:
- from services.msc stop "Windows Management Instrumentation" service
- go to Start -> Programs -> Accesories
- right click on "Command prompt" and choose "Run as administrator"
- issue the following commands:
cd /d %windir%\system32\wbem
ren repository repository.old
- start "Windows Management Instrumentation" service
You'll probably have to reboot after these runs.