If a server is having problems that require the services to be cycled, continue to monitor the server after it is online. The problem may reoccur many times. This happens most often with MTA and information store problems.
If you are unable to determine whether the server is behaving normally, log on using the server's test account and send some test messages. Verify with the target recipient that the test messages have been received.
Sending messages between the test mailboxes using delivery receipts is a useful way of verifying server-to-server communications.