you will find the log under
C:\Program Files\Symantec\Symantec Endpoint Protection Manager\tomcat\logs
whats th size of sem5.log? do you have any backup?
if yes then go to services.msc
find the embedded db service
make it to disabled. click apply , click OK
open the task manager, kill the dbsrv9.exe or dbrsrv12.exe ( based on the version)
go back to services.msc check if you can start that service.