Mail server not working with Postfix Dovecot

Mariano Jara Melagrani mjaramelagrani at
Mon Dec 7 17:15:17 UTC 2015

On 07/12/15 12:06, David Fletcher wrote:
> On Mon, 2015-12-07 at 11:49 -0300, Mariano Jara Melagrani wrote:
>> On 07/12/15 01:58, David Fletcher wrote:
>>> On Mon, 2015-12-07 at 00:48 -0300, Mariano Jara Melagrani wrote:
> I can give you help with configuration, as can others, but as has been
> pointed out you really need to know whether or not your ISP blocks
> ports.

I've recently talked to them over the phone, and they say they don't
block ports 25 and 110. They suggested to restart the modem, which I
did, but nothing is coming in so far.

> A very quick search found this for me:-
> which I just tried out and it appears to give accurate results. I do not
> know, though, if it only gives a positive response if the port is
> forwarded by the router AND there is something on the network listening
> on that port. If, for instance, you want to check that IMAP and IMAPS is
> working then install dovecot, enable the protocols and test it. Or
> apache might be easier for starters. I don't think you need to configure
> anything to see a response to a web browser.

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?

> 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.

Mariano Jara Melagrani

0x80319128 GnuPG v1.4 (GNU/Linux)

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