I upgraded ok, from 3.9g to 5

I can send and receive emails from my server, but when I try and send them through Zen I get nothing. No message, just confirmation they have been sent.

I have tried changing the settings, created new email addresses to test, made sure no filter or spam blocker was on but still nothing.

I can use contact, newsletter and all functions, but the emails don't appear at the receiver.

Thoughts ??? Help ???