Groupwise GWIA version: 6.5.7
Platform: Netware 5.1
Received non-deliverable error for outbound email to partner's internet domain...Other internet domains were ok. Inbound email from partner's internet domain were ok.
Transcript of session follows:
Response: 420 TCP write error
I have done a search on google and read thru the following links. Done a spamhaus check to ascertain that our outbound smtp public ip was not blacklisted.
Done a telnet to partner's internet domain and returned a "Connect failed" (presumably they have blocked any incoming telnet to their SMTP gateway)
Please advise further troubleshooting steps to identify cause of non-deliverable emails to only certain internet domains.