I setup a fresh centos server with just apache and PHP. I disabled iptables. But it still says my port 25 is blocked by firewall. Is there something I have to install or enable to get it to allow the post 25 connections through PHP?

To open the port 25 for external connections, do this:

Go to WHM -> Tweak Settings -> SMTP Tweaks -> Mail.

Set “Restrict outgoing SMTP to root, exim, and mailman (FKA SMTP Tweak)” to OFF.

Then go to “ConfigServer Security&Firewall” -> SMTP Settings.

Set SMTP_BLOCK to 0.

Save the changes.

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