Asa 5540 version 7.0(7) in front of exchange 2003 enterprise with the latest service pack, and GFI antispam box, queue builds up almost on daily basis, and we have to reload the firewall in order the get the email flowing, it works for a day then it happens again.
no changes have happened since this started , we have relay taken care of already long time ago and we are good in that aspect. Also, "no fixup protocol smtp 25" was applied via command line on the firewall.
when I try to connect to our mx records' ip address from outside, i got "Could not open connection to the host, on port 25", if I do smtp test on mxtoolbox i get "
Connecting to 173.161.x.y
I'm the only administrator in the company, I have not made any changes for the past 6 months not even patching the exchange server. and everything was working fine until 4-5 days ago.
we confirmed in a previous question that it is a firewall issue not exchange, Please see question ID28389705.