Mail server not working with Postfix Dovecot

Petter Adsen petter at
Mon Dec 7 17:33:51 UTC 2015

On Mon, 7 Dec 2015 14:15:17 -0300
Mariano Jara Melagrani <mjaramelagrani at> wrote:
> I've tried the tool on the site you suggested and I've got these
> results:
> Port 25 is closed on
> Port 110 is open on
> Port 465 is closed on
> Port 995 is open on
> I've got ports 25, 110, 465 and 995 in forwarding state on my border
> router, since I must use NAT, so they're open to the world, right?
> And my server is listening on these ports
> So, does this mean that my ISP is lying when they affirm that they
> don't block port 25?

Set the router to log any packets it forwards on those ports, then try
again. If you see packets being forwarded in the firewall logs, then
there is a problem behind it. If you don't, your ISP could be lying.

And make sure to reload the configuration on the router first. Reboot
it, if necessary, to make sure the changes are applied.

> > The other thing I think I should say is, I hope you're fooling
> > around with a test machine here, rather than one that matters to
> > you. A test machine can easily be a virtual machine.
> No, unfortunately I'm doing on my production server. I don't know if
> it's up to run a virtual machine, since it's a very low spec PC. It
> used to be a desktop PC and it probably has more than 20 years old.

Running a full VM on that would probably be painful, yes. You might get
away with a lightweight container, but others here would know better
than me what that requires.


"I'm ionized"
"Are you sure?"
"I'm positive."

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