If the Database service will not start then the Symantec Endpoint Protection Manager service will not work properly. The database files need to be repaired before the Database service will start. The following procedure should repair any damage.
In the Command Prompt type: "CD C:\Program Files\Symantec\Symantec Endpoint Protection Manager\ASA\win32\" and press Enter this will change directories to the folder containing dbsrv12.exe.
To force the recreation of sem5.log. Type: "dbsrv12.exe -f "C:\Program Files\Symantec\Symantec Endpoint Protection Manager\db\sem5.db" and press Enter
Click Start, click on Run and Type "services.msc" then click OK and start the "Symantec Embedded Database" Service
Start the Symantec Endpoint Protection Manager service
Once the service is started then a database backup can be restored if required.