WordPress can't connect with smtp server

jobbe

Hello

Yesterday I transferred me mails from virtualmin to mailcow, before that I tried to follow the mailcow docs as best as I could. I have already managed to solve ssl certificate issues I was getting with outlook (certificate not trusted) but now I am stuck connecting in wordpres to the smtp server.

With the wordpress plugin Post SMTP I can do checks to the smtp server, there I get following results:

So there it seems he can’t reach that smtp server, sending a test mail doesn’t work either.

If I then set port 587 on my router back to my previous mail server for a while, it does work (old and new mail server are within the same network), there I get following results:

Sending mails through the webmail and through outlook works perfectly so I don’t really know what to do at this point or where to start looking for errors/debugs.

Can anyone help me with this?

Thanks in advance!

DocFraggle

Is there a firewall service running on your mailcow host? The ports are shown as open because you are forwarding them on your router, I guess the firewall on your computer running docker may be active and is blocking incoming requests

jobbe

DocFraggle ufw is running on the mailcow host:

EDIT: If i disable UFW, I still see the "No"s in the test.

DocFraggle

Hm, did you restart docker after disabling ufw? Maybe even reboot the whole system, it’s possible that the iptables configuration has to be reapplied.

Otherwise have a look at the docs at https://docs.mailcow.email/prerequisite/prerequisite-system/#firewall-ports and check the ports and the running services

jobbe

DocFraggle Thanks, I saw that ufw should be disabled so I removed ufw and rebooted the system. These are the running services:
LISTEN 0 4096 0.0.0.0:4190 0.0.0.0:* users🙁(“docker-proxy”,pid=1277,fd=4))
LISTEN 0 4096 0.0.0.0:993 0.0.0.0:* users🙁(“docker-proxy”,pid=1509,fd=4))
LISTEN 0 4096 0.0.0.0:995 0.0.0.0:* users🙁(“docker-proxy”,pid=1351,fd=4))
LISTEN 0 4096 0.0.0.0:587 0.0.0.0:* users🙁(“docker-proxy”,pid=1134,fd=4))
LISTEN 0 4096 0.0.0.0:110 0.0.0.0:* users🙁(“docker-proxy”,pid=1792,fd=4))
LISTEN 0 4096 0.0.0.0:143 0.0.0.0:* users🙁(“docker-proxy”,pid=1597,fd=4))
LISTEN 0 4096 0.0.0.0:465 0.0.0.0:* users🙁(“docker-proxy”,pid=1204,fd=4))
LISTEN 0 4096 0.0.0.0:25 0.0.0.0:* users🙁(“docker-proxy”,pid=1322,fd=4))
LISTEN 0 4096 [::]:4190 [::]:* users🙁(“docker-proxy”,pid=1295,fd=4))
LISTEN 0 4096 [::]:993 [::]:* users🙁(“docker-proxy”,pid=1522,fd=4))
LISTEN 0 4096 [::]:995 [::]:* users🙁(“docker-proxy”,pid=1357,fd=4))
LISTEN 0 4096 [::]:587 [::]:* users🙁(“docker-proxy”,pid=1140,fd=4))
LISTEN 0 4096 [::]:110 [::]:* users🙁(“docker-proxy”,pid=1802,fd=4))
LISTEN 0 4096 [::]:143 [::]:* users🙁(“docker-proxy”,pid=1606,fd=4))
LISTEN 0 4096 [::]:465 [::]:* users🙁(“docker-proxy”,pid=1217,fd=4))
LISTEN 0 4096 [::]:25 [::]:* users🙁(“docker-proxy”,pid=1328,fd=4))

But connecting from outlook does work, via WordPress does not.

jobbe

I did some extra tests on another website and then I got the correct outputs:

The wordpress website it is not working on is on a vm in the same network as the vm the mailcow is on. Apparently that would cause problems?

jobbe

I fixed it, thanks!

Olgaa

Can you please tell me how you fixed it? I am encountering the same issue 😕