Environment
SUSE Linux Enterprise Server 11
SUSE Linux Enterprise Server 10
Novell Open Enterprise Server 11 (OES 11) Linux
Novell Open Enterprise Server 2 (OES 2) Linux
Novell Open Enterprise Server 1 (OES 1) Linux
Novell GroupWise 2012 Novell GroupWise 8
Situation
Mail is not getting delievered to one post office even though the MTA shows the post office as open. Message files are building up in the domain's MSLOCAL/MSHOLD queue for that post office.
Resolution
This can happen when there are multiple MTA's loaded for the same domain. Sometimes when an MTA is unloaded the GroupWise High Availability Agent (GWHA) will load a second instance of the MTA before the admin reloads the MTA. This can result in two MTA's being loaded for the domain at one time. They act independently of each other, but are not totally aware of the files in each others queues causing them to loop or prevent delivery to the post office from occurring.
Check for duplicate MTA's for the same domain from a terminal session by typing "ps -eaf | grep gwmta". If there are multiple instances, kill them both and restart the MTA.