Check WMI Repository

Check if the repository is corrupted or not by running following command from command prompt with admin rights:

winmgmt /verifyrepository

If it is corrupted the returned result will be Repository is inconsistent.

If it comes back as consistent, then repository is not corrupted so do not rebuild repository at this point.

As a final note, if you are running into a reoccurring WMI corruption issue in your environment, try to exclude the WBEM folder and all subfolders under it from AV scanning. AV scanning is known to cause corruption in WMI.

http://blogs.technet.com/b/askperf/archive/2014/08/11/wmi-missing-or-failing-wmi-providers-or-invalid-wmi-class.aspx