This week I ran into a strange issue where one of my servers agent accounts would not start up. The SQL Server and the SQL Agent both use the same domain account and the Server was running just fine. The error in the event viewer was a bit strange. It was the following error:
SQLServerAgent could not be started (reason: Unable to connect to server ‘Some Strange Name'; SQLServerAgent cannot start).
After looking into this I found that someone had modified the SQL Server Agent connection properties withing SSMS and had put the ‘Some Strange Name’ into the Alias Local Host Server field. After looking up what that field does, http://msdn.microsoft.com/en-us/library/ms175176.aspx, I decided that I did not have to have anything in that field. I removed the entry, hit OK and then tried to start the service and what do you know. It all works now.
Hope that helps if anyone else is having issues like that.