I have set-up a "Restricted Word" filter in GMS Anti-Spam to prevent disqualified messages from reaching a mailbox. It works perfectly. I have noticed that when I select the option "Return message to sender", the e-mail is never returned to any of my local users. Only external users and the local Postmaster account ever seem to have an e-mail returned.
Why is this?
The fact that the user is not receiving a returned e-mail illustrates that GMS Anti-Spam is functioning correctly. As explained above, GMS Anti-Spam detects the restricted word in the message and does not allow it through – either inbound or outbound.
The sender in your domain does not have the message returned because it still includes the restricted word. GMS Anti-Spam is correctly blocking the attempt to return the message back to the sender. To explain further, when you select the option "Return message to sender" GMS attempts to send the exact incoming message back to the sender. As the sender is on your local server, and the content of the message is banned from entering your server, it is not possible to return the message.
To explain further, the message is rejected due to restricted content, a warning message is returned to the original sender. This warning message also contains the restricted content and is therefore also rejected.
The Postmaster account is set-up to allow such messages through in order to allow contact to be maintained with senders who suspect their messages are being incorrectly blocked.
Keywords:Anti-Spam restricted sender returned JUCE Spam checker GMS anti spam antispam