I have the following situation:
Exchange2000 which will fetch the mail from a bSMTP-server somewhere else.
It was all working fine, till a month ago, then a lot of emails were not arriving at our server.
I called with the ISP and other people, and I narrowed the problem to the following:
When I telnet the server from the local network at port 25, I get the expected reaction like 'ESMTP Exchange Microsoft.......'
But when I telnet the server on port 25 from the internet, then the server disconnects the telnet session in half a second.
When I do above for port 110 (POP3) there is no problem. I removed all the rules in the firewall.
Sometimes an email will arrive...
Please help me, cause all my colleagues are complaining about this problem