Answer
GMS was operating the smart redirect rules and a rule matched that requested that the remote server should attempt to try sending the message again later. The rule was executed before the message was completely delivered (to save bandwidth).
The smart rules are processed in order until one of the rules are matched. Once a rule is matched it is immediately actioned and all processing of the smart rules are stopped for that message.
In this case, session Undefined was using the rule which matched the parameters
- Undefined = Source server/client IP address;
- Undefined = MAIL clause (the protocol FROM details);
- Undefined = Local IP address that the message was delivered to (this may be different for multi-homed systems); and
- Undefined = RCPT clause (the protocol TO details).
- The protocol response was
Undefined
This is the correct result, no action is required by you.
See Also:
- How do I block a single email address ?
- What Is Mail Meta Language (MML)?
- How do alerts work?
- What is SMTP Response Code Theory?
Keywords:redirect rules retry 8340