Description |
This article describes how to troubleshoot 'Error 421 4.7.0 too many 'NOOPcommand; closing connection'. |
Scope | FortiMail. |
Solution |
'NOOP' stands for 'no operation'. Useful mostly in testing to avoid timeouts. The log will be similar to this in FortiMail:
Solution: In Profile -> Session, select the current session profile or create a new one, expand the SMTP Limit, and increase the Maximum number of NOOPs allowed for each connection:
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