We are in the process of going from V5R4 (our old 520 iSeries) to V7R1 (our new shiny E4B iSeries) but sending mail did not work. Getting weird messages in QSYSOPR. After all my ideas were exhausted I was lucky in the last seconds before giving up and handing it over to the IBM guys. It appears that the CHGSMTPA command in V7R1 has some new parameters/keywords, FWDHUBSVR being one of them. Freshly added keywords get a default, in this case *NONE, and that appeared to be the villain.
Giving FWDHUBSVR the same value as MAILROUTER solved all my problems (why this new keyword was introduced/needed and why IBM didn’t gave it the default value of the MAILROUTER value I don’t know, but this problem gave me a real headache for 2 days)
CHGSMTPA MAILROUTER(‘10.100.10.103’) FIREWALL(*YES) FWDHUBSVR(‘10.100.10.103’)