Can’t initiate manual scan with Symantec Endpoint Protection

Received a call yesterday that the users can no longer start a manual virus scan on their workstations.  Clicking the Active Scan or Full Scan options on the Scan for Threats dialog produced nothing. No scan, no error, nothing.

All clients are running Symantec Endpoint Protection 11 MR4 and the policies on the SEP server have not been changed. Virus definitions are coming down fine, admin scans are running, it’s just the users can’t start a scan manually.

What caused it?

Well,  I decided a couple of weeks ago to set my GPO to ensure that all of the Symantec services could not be stopped by our users, which are Power Users to their local workstations. I simply Enabled the policy and set the services to Automatic. Obviously, it was doing something more to one or more of the services. Once I went back into the GPO, disabled those settings, and let AD replicate out, the users were able to once again initiate virus scans.