Answer
A message is bouncing between two or more message servers and is unlikely to ever be delivered. Therefore GMS has stopped the loop and is returning the message to the sender.
In this case, session Undefined was processing a message from a server at Undefined. The message was apparently from Undefined to Undefined and the message will never be delivered to Undefined so it has been returned.
You will need to investigate why the message cannot be delivered to Undefined.
See Also:
- Why am I getting an “Exceeded Hop count” failure email?
- Why do I get message has exceeded maximum number of hops?
- How do alerts work?
Keywords:exceeded hop count 8288