So a few weeks back we had an issue where we would get this error
Error 5: Access denied
If the event log service is down troubleshooting things can be a bit tricky, plus the SMTP service depends on the Event Log service, which was a problem for us as we use the SMTP service heavily.
In our case, we had an error that indicated that a dependent service had not started and thus this service could not start. This is where it gets interesting.
The Event Log service had no dependencies, at least as far as the services console would suggest and yet the error suggested that there were dependencies.
After a while we looked at this hive in the registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog
Lo and behold, there was a dependency
Namely DependOnService was populated with a non-existent service, which is why I guessed that it wasn't being displayed on the services console.
So we deleted the key and the service started.