Hello.

I have tried to connect my OSticket application that, before the Zoho Mail implementation, was OK using the same email address, but never using PHP mail function (there's another post that solved this issue using that function).

I have been getting this error (attached). I have verified the access to the mailbox through Zoho Portal using user/pass settings and all is OK. Even the Two Factor Authentication is off, and POP is ON.

So, what is the problem?