The Symantec Endpoint Protection service fails to start at system startup, the following entry can be seen in the System Event log:
System Error Service Control Manager Hostname 7009 A timeout was reached (30000 milliseconds) while waiting for the SepMasterService service to connect.
Starting the Symantec Endpoint Protection service manually successfully starts the service.
On some busy systems where many services are starting, it is possible that the SEP service (and potentially other services) will fail to start within the allocated time window.
.It is usually enough to increase the time out period on service startup, this can be achieved by following the Microsoft documentation below
A slow service does not start due to time-out error in Windows