Error on Outlook for Android with IMAP

marcofons

Hi,

We’re having some trouble to configure an email account on Outlook mobile app for Android using IMAP.

When we setup the email account on Outlook using IMAP, we see this message on Netfilter log and Outlook gives an error message like “Can’t logon”:

170.x.x.x matched rule id 4 (warning: non-SMTP command from unknown[170.x.x.x]: \026\003\001\002\000\001\000\001\374\003\003_\340u2q\0039\375-\362\207\312\203\005\360W_\205\2134#\2)

Where 170.x.x.x is the IP of the Android device.

DocFraggle

marcofons 170.x.x.x matched rule id 4

This could mean the client was blocked by fail2ban due to a configuration issue or wrong password.
Check the fail2ban page

esackbauer

marcofons rule id 4 (warning: non-SMTP command from unknown

Are you sure you are using the right ports. If you try to use IMAP to a SMTP port like 587 then I guess that error makes sense.

marcofons

DocFraggle thank you for your answer, but the password is correct and I didn’t change any config in fail2ban

DocFraggle

I meant you should look if the IP is listed on the fail2ban page

marcofons

DocFraggle no, IP it’s not listed on fail2ban. This happens only when configuring IMAP on Outlook for Android app

DocFraggle

esackbauer If you try to use IMAP to a SMTP port like 587 then I guess that error makes sense.

Good catch, I didn’t think of that! @marcofons which container produced the logs above? If you got that from the Postfix container you are definitely using the wrong port. IMAP is 143, IMAPS is 993

marcofons

esackbauer Thank you for the hint. Problem was on the protocol when adding account on Outlook, we were using SSL on 587, but we should use StartTLS instead, now it works