Error: 550 Host unknown (/maxdeferhours=96)

  • 3020709
  • 31-Oct-2006
  • 26-Apr-2012


Novell GroupWise 7
Novell GroupWise Internet Agent (GWIA)


Error: 550 Host unknown (/maxdeferhours=96)
Unable to send any outbound messages.
Users getting undeliverable message on every outbound message.


Open GWIA.CFG file.
Look for the switch "/mh="
Remark out this switch in GWIA.CFG.
Restart GWIA.
In this case /mh switch had no IP Address or DNS Name associated with it and was followed with another switch /maxdeferhours=96. GWIA was trying to relay mail to a Host Name of /maxdeferhours and failing.
The /mh switch specifies the IP address or DNS host name of a relay host that you want the Internet Agent to use for outbound messages.

The /maxdeferhours switch overrides the number of hours after which the Internet Agent will stop trying to send deferred messages. The default is 96 hours, or four days. A deferred message is any message that couldn't be sent because of a temporary problem (host down, MX record not found, and so forth).