After upgrading to Symantec Endpoint Protection (SEP) 14.2 RU1 MP1 users are unable to access MMC snap in applications such as Active Directory Users and Computers, Windows Event Viewer, Services, or launch mmc.exe itself. Windows updates will also fail on install. There will be repeated CAPI2 errors in the Windows Event Viewer: "The Cryptographic Services service failed to initialize the Catalog Database. The ESENT error was: -1805"
If you are logged on as a local Administrator and open an elevated Powershell command prompt (Run as Administrator), starting any of those above applications or mmc.exe directly will be successful.
This app has been blocked for your protection. An administrator has blocked you from running this app. For more information contact the administrator.
A hotfix SEP 14.2 RU1 MP1 b4815 has been released to resolve this issue. This build is available for download on My Symantec. SEP 15 client packages have been refreshed to include this fix and are available now.