How do I configure custom SMTP server?

[newuser1]

I just setup the 3CX software (free version) but when I go to settings and try to change my mail settings the type of email server is grayed out with 3CX SMTP server selected. If I click on test with 3CX selected I get error, AuthenticationInvalidCredentials: 5.7.0 Denied. Is it possible to change SMTP server if not how do I correct the authentication problem?

 

[newuser1]

I corrected the mail auth issue by changing my SNAT to the correct public; however is there a way to change the server to internal?

 

[Saqqara]

You can not change the SMTP settings in the free version.

You need a commercial license to use your own SMTP server

 

[apostolis_3CX]

That is correct, starting from V15.5 SP2, using your own SMTP server requires a commercial License Key.