I am hoping to get some idea where to go from here to resolve the sporadic issue of not connecting to remote mail servers. When there are several emails addressed to the same domain or a message is sent to a large number of emails, invariably some of them come back with "450 Host down", yet gwia has sent the first or second occurrence of those emails, (with like domains), but then the rest don't go.

We have GroupWise 2012 with SP1 on a SLES 10 SP4 dedicated server. Everything else is with in given parameters and we could go for several days to weeks with out the dreaded Host down message appearing.

I did go into C1 and set the "Intervals to retry a deferred message" to: 3,10,20,20,20,60
That did seem to help a bit with connection to mail server (before it was 20,20,60).

I thought about building the route.cfg file but I am unsure if this would be the answer, currently it's not used.
We don't relay our messages to another server; they are direct connections to other mail servers.

Any tips/advice on what I can do to resolve this is appreciated.