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External mail client cannot connect to server
#1
External mail client cannot connect to server
Hello

So, I've finally setup the postfix on my server and setup TLS. Everything is working fine in regards to receiving, sending mail and being encrypted, but not when I want to connect to the server from an external email client like i.e. Outlook. Error message is a bit vague but it says that the imap settings
are wrong.

How do I define the imap and smtp addresses and possibly the ports as well?
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#2
RE: External mail client cannot connect to server
as an update to this issue:
Due to the lack of support here... I was planning to scratch sentora and replace it with another opensource panel... until:
TLDR
Issue 1: dovecot uses 143 for STARTTLS. All guides said to use 993 which is why I kept diagnosing with this port.
Different websites claiming to be able to test dovecot connection were coming back with a positive connection, even when on one of the websites I wrote port 993. Port 993 should have never worked, and with a telnet test from windows, I basically confirmed that 993 does not work (with how the configs are for dovecot).

Issue 2: ..... I never thought, while paying for a office 365 that I would have such a problem with an issue that shouldnt exist.
There is a bug with Outlook that makes it fail to create a Data File when adding the account with the simplified version of the "add account" dialog. I have other IMAP emails (gmail/hotmail) added in Outlook and they worked fine adding them through the simplified dialog, which is weird. By finding the "secret way" to access the old version of the add account dialog, it added the account without problems.
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#3
RE: External mail client cannot connect to server
An update for this thread:

Outlook for android forces the use of port 465 (SMTPS) and port 993 (IMAPS) for encryption and wont work with any other ports like, 25, 143, or 587. This isn't mentioned anywhere official and took a while to find this info.

If you try to manually force those three ports, It will simply deny the certificate or wont load the account at all.

You will need to setup SMTPS in the master.cf file  if you havent done so and enable SMTPS and IMAPS ports with your firewall
Code:
smtps   inet    n       -       n       -       -       smtpd
  -o syslog_name=postfix/smtps
  -o smtpd_tls_wrappermode=yes
  -o smtpd_sasl_auth_enable=yes
  -o smtpd_client_restrictions=permit_sasl_authenticated,reject
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