Connection to SMTP Server

[denverdataman]

I am very confused. When I look at ip_out port 587 is open for outgoing traffic. However when I try and send mail through several different web applications it fails. If I turn off the firewall than it works perfectly.

I have tried port 25 as well and I get the same result.

What is even more confusing to me is that if telnet to smtp.sendgrid.net 587 then I can connect even with the firewall enabled.

Any ideas and help is greatly appreciated.

Thanks,
Steve

[denverdataman]

The best solution I found was to remove port 587 from the list of SMTP ports. Not the best solution but it appears to be working.

I had tried giving permission to specific users on the server to use SMTP but this did not work either. So this is the best solution I have.

[Lineikosen]

I spent so much time on issues like that, I might be able to help you Earth1 if the tool from my previous post doesn't show port as blocked.

[Sergio]

Are you using cPanel?

If so, then go to SERVICE MANAGER and check on "Exim Mail Server (on another port)" if you have listed there the SMTP ports that you want to use.

After that, go to CSF and check your TCP/UDP IN/OUT if the ports are set there. Also, check in CSF:
SMTP_PORTS =
and write there the ports that you declared in SERVICE MANAGER.

Hope that helps.