There is no difference in the installer for Xeams Community and Enterprise Edition. It will run as if you have purchased the Enterprise Edition for the first 30 days. It will then get converted to Community Edition unless a license is purchased.
We have several mail servers (2-3 for sending and 1 for receiving). When there is NDR, it is delivered inbox on another server which mark the NDR as SPAM because: KAM_GB_INVALID_FROM
Xeams generate NDR with header:
From: postmaster
