Firewall Rule "mail content scan" - Mail filter policys

Hi there,

i use XG 18mr4 and have a troubleshoot question i cant find in documentation.

if you create/modify a firewall rule, at the bottom you find "mail content scan". Does this depend or activate on the mail filter policys i can configure seperatly?

When i activate the 6 buttons for "mail content scan" i get an mail client error massage with the certificate i receive.

scenario: behind my XG there is an mailserver (generated LE certificates), openend via DNAT through the XG, the mailserver covered by a firewall rule with the "mail content scan" enabled buttons. So if i try to reach the mailserver from web (not lan), i receive a sophos related certificate error on my IOS device.

thanks in advance