Fire up regedit and find this key:
With "Eventlog" highlighted on the left pane, you should be able to see a value called "ImagePath" on the right. ImagePath should be equal to this:
%SystemRoot%\System32\svchost.exe -k LocalServiceNetworkRestricted
If you can't see "ImagePath" in that location, or if it's not set to the text above, that's almost certainly your problem. If you're in the habit of using "registry cleaners", that might be the cause.