Till, I must apologize for my above cockyness...which was probably the cause of your snootyness...I understand everything you were saying, it just seems...being my expertise is in programming...I have hosted servers eons ago (in the 90s) and the technology has changed in ways someone from my day can barely comprehend. I realize that if I send myself an email and receive it, then pop3 is functioning properly...which as you were attempting to explain...that port 25..the port I use to successfully send email...has to communicate with an email server on the other end at the same port...port 25...if i can use port 25 only asynchronously, then I can communicate out on this port, but not in...
root@webserver:/# netstat -tap | grep smtp tcp 0 0 *:smtp *:* LISTEN 27094/master tcp6 0 0 [::]:smtp [::]:* LISTEN 27094/master
What you tested with squirrelmail is that port 25 is working fine on the server itself (localhost). This step is important to find out if the issue is on the server or in front of the server (isp / firewall / router). So we know now, that the mail system on your server is working fine as the mail took the full rountrip (port 25 in, mail scanner with amavis and clamav, delivery to the mailbox and fetching with imap). The netstat result above shows also that port 25 is open on the external network interface (and not just localhost), so that's fine as well. To sum it up, your mail server system is installed correctly and working fine. But the problem remains. So we can limit the problem to something that is between the server and the internet, because neither I nor @Croydon is able to connect to your server on port 25 and I made the test form a mail system in a datacenter, so there is no problem on my side of the conection. Here are the next steps: 1) If you like to try it out yourself what we did to test your server, run this: telnet localhost 25 you should receive a mail prompt then (if telnet command is not installed, install it with apt). You can leave that prompt with the word 'quit'. You can replace the word localhost with the internal server IP though. I'm quite sure that this will work as squirrelmail will have failed otherwise. 2) If 1) works, then the problem is that this works from your server but not from outside, here the possible reasons again: 2.1) A firewall on the server that blocks port 25, check that with: iptables -L 2.2) A router in front of the server where you did not forward port 25 (outside) to port 25 (on the server). 2.3) A firewall or other system at your ISP which blocks port 25 incoming.
right i know how to use telnet...that was around in my day ...I will check the firewall as you suggest...and yes, when I connect to 25 through telnet, i have no problem, but as you mentioned, that is only one direction.
interesting...now i feel like a knob...the issue is now resolved rofl...while testing...i blocked incoming port 25 on my router...i just unblocked it and im receiving email now duhh...thanks for your patience...you and your friend.
im only going to be 51 in a week...interesting how the brain doesnt operate as well even only at this age
ok I see what the issue is, but how to fix it. squirrelmail is sending email that the receiving servers are identifying as spam...as noticed by the email I sent to my wife's hotmail account and my friends email account...hotmail identified its antispam software as spamhaus...etc...meh problems...
Ensure that the external IP address of your server has a valid reverse DNS record that points to the hostname of your server. This record has probably to be set by your business line provider. Beside that, you might add an SPF record in your domain and you should check if your IP address is on any MX blacklists.
