Issue with custom SMTP server

[gustavskii]

Hello after update we cannot connect to our SMTP server, and send emails
Here is the issue:
No compatible authentication mechanisms found.
The were no changes made neither to the settings of 3cx (except update), nor to mail server, nor to firewall settings

 

[MichaelTC]

I have the same issue, I went with a gmail work around until this gets fixed.

 

[accentlogic]

We found this happened when SP2 was released and 3CX started enforcing TLS 1.2. That could be your issue, especially if you are using alternate ports. (Other than 465. Even 587 was an problem for them.)

 

[gustavskii]

We found this happened when SP2 was released and 3CX started enforcing TLS 1.2. That could be your issue, especially if you are using alternate ports. (Other than 465. Even 587 was an problem for them.)

Here is the error we get when we use TLS:
Connection timed out: Ensure that Port 465 TCP is open for outbound traffic.

 

[gustavskii]

@accentlogic
Thank you, you were right
We were using 587 port, and our firewall didn`t have rule for 465
As soon as we enabled 465 and set it as connection port, it started working