v16 - Custom SMTP Server stop working

[alerti.support]

After upgrade to v16 notifications stop working. When I check SMTP server configuration and run a TEST show the message "Incorrect authentication data".
I confirmed the SMTP server, login, password and port but the message is generic. Any idea? Anything changed int this configuration?

3CX SMTP Server works great.

Mail Server - CPanel

 

[cobaltit]

Yes, use the 3CX SMTP server . 3CX can't test all SMTP servers, so the only thing guaranteed to work is 3CX SMTP, Google and Office 365. If you run your own SMTP servers then you should be able to get logging from there that will tell you why it's not working, as well as adjust it so 3CX works with it. Otherwise you get to use one of aforementioned options.

 

[alerti.support]

I am concerned that such a change will occur in a version update without warning.
Until the last version worked normally.

I want to use @mydomain not 3CX Server. Other 3 softwares use the same SMTP Server (TLS/SSL authenticated) and works fine.

 

[cobaltit]

I'm not sure I understand your concern. Do you not update software ever? All software has updates, this is no different. Just because something else works with your SMTP server doesn't mean anything. 3CX could have eliminated less secure TLS options which is why it does't work. Remember 3CX isn't building a SMTP client from scratch, they are using a pretty common library for this. But again, you have your options. You can use one of the three options that would always work because they are tested, or you can look at the logs on YOUR server to figure out why it isn't working and then adjust YOUR server. That's one of the reasons folks run their own server is to have that flexibility.

Wanting alone isn't going to fix the issue.