Try the following:
1. Right-click My Computer.
2. Press the Manage item.
3. Double-click Services and Applications in the left-hand pane.
4. Press Services to expand it.
5. Scroll to Windows Management Instrumentation in the right-hand pane and right-click it.
6. Press Stop.
7. Use Windows Explorer to delete all the files in the %SystemRoot%\System32\Wbem\Repository folder.
8. Shutdown and restart your computer. The Windows Management Instrumentation service will start and the files will be re-created.