Event 7031, Service Control Manager, The Microsoft Mailbox Assitants Service terminated unexpectedly

I have received the following event ID on and Exchange 2010 SP1 mail box server.

Event 7031, service control manager.

The microsoft exchange mailbox assistants service terminated unexpectdly. It has done this 1 time (s). The following corrective action will be takein in 5000 milliseconds: Restart the service.

I am look for a potential cause for this and a resolution if one is known.

Thanks