Issue Trouble Adding IMAP Email Accounts on New Version of Outlook

[Rabah]

Server operating system version

CentOS 7.9

Plesk version and microupdate number

Version 18.0.58 #2

Hi everyone,

I'm experiencing some difficulty adding IMAP email accounts on New Outlook, which now supports IMAP. Interestingly, this seems to be happening only with my domains hosted on my servers running Plesk Obsidian CentOS 7.9, with a mail server setup of Postfix and Dovecot.

Strangely, I have other mail servers (using Sendmail) where my IMAP/SMTP email accounts add seamlessly on New Outlook.

Has anyone else encountered this issue or have any insights into what might be causing it?

Thanks in advance for any help or suggestions!

 

[Peter Debik]

What error message do you see in Outlook?
What log entries do you see in /var/log/maillog at the same time on your server?

 

[Rabah]

Hello, on Outlook it just says "An error occurred while configuring the account, try again later,"

but in /var/log/maillog, the error is:

postfix/smtpd[8247]: TLS SNI mydomain.com from unknown [52.125.132.46] not matched, using default chain
postfix/smtpd[8247]: TLS SNI mail.mydomain.com from unknown [52.125.132.46] not matched, using default chain

Please note that the MX records for mydomain.com are mail.mydomain.com. This is a shared server with multiple domains hosted on it.

 

[Rabah]

What error message do you see in Outlook?
What log entries do you see in /var/log/maillog at the same time on your server?

Hello, on Outlook it just says "An error occurred while configuring the account, try again later,"

but in /var/log/maillog, the error is:

postfix/smtpd[8247]: TLS SNI mydomain.com from unknown [52.125.132.46] not matched, using default chain
postfix/smtpd[8247]: TLS SNI mail.mydomain.com from unknown [52.125.132.46] not matched, using default chain

Please note that the MX records for mydomain.com are mail.mydomain.com. This is a shared server with multiple domains hosted on it.

 

[Rabah]

Could it be that the server doesn't find a matching certificate for mydomain.com and Postfix uses the default certificate chain instead and causes mismatch errors ?

 

[Peter Debik]

Yes, but it won't keep Outlook from creating the account. Are you sure that you have entered the correct mail server name in Outlook and that the computer can access that address on outgoing and incoming mail server ports?

 

[Rabah]

Yes, but it won't keep Outlook from creating the account. Are you sure that you have entered the correct mail server name in Outlook and that the computer can access that address on outgoing and incoming mail server ports?

Well it`s seems like the server couldn't find a matching certificate for the requested domain name (Here mydomain.com), so it fell back to using the default certificate chain. I just issued a valid SSL certificate through Let's Encrypt for mydomain.com / *.mydomain.com, and I successfully added my address [email protected] to New Outlook without encountering any of this errors:

postfix/smtpd[8247]: TLS SNI mydomain.com from unknown [52.125.132.46] not matched, using default chain
postfix/smtpd[8247]: TLS SNI mail.mydomain.com from unknown [52.125.132.46] not matched, using default chain


Now the question is, what about other domains for wich i can`t install an SSL certificate ... ? Cause it`s seems like even if i try to add mail accounts on New Outlook without using any encryption method (SSL/TLS) using ports 143 IMAP and 587 SMTP, i still get the errors....

 

[Peter Debik]

The SNI log entries are irrelevant. You can ignore them. They are just "notices", but will not block anything.