Uh, so… you email “client” is AltN MDeamon mailserver? :o Well, let me start with this - the version of avast! you are using is not intended to be run on (mail)servers.

Other than that - go to Settings - Troubleshooting - Redirect settings and remove all ports in the Mail section there. Preferably you should uninstall mailshield altogether. Then again, using avast! free in this way on servers is not suitable and also in breach of the license.