There are times when you receive a message with a delivery status of Allowed/Whitelisted, a delivery status of rejected, and the delivery detail states 550 5.7.1 Message rejected as spam by Content Filtering. This indicates that the message was blocked by the receiving Exchange server's Content Filtering feature. In order to disable the SPAM filter functionality on Exchange, follow these steps:
1. Start System Manager: On the Start menu, point to Programs, point to Microsoft Exchange, and then click System Manager.
2. Move to the SMTP virtual server, starting with Servers.
3. Right-click the SMTP virtual server, and then click Properties.
4. On the General tab, click Advanced.
5. In Identification, clear the Apply Intelligent Message Filtering check box, and then click OK. In Advanced, under the Filter Enabled column, No appears.
1. Open the EMC on the Edge Transport server.
2. In the console tree, click Edge Transport.
3. In the work pane, click the Anti-spam tab, and then select Content Filtering.
4. In the action pane, click Enable or Disable as appropriate.
It is now stated in the quick start guide: "Barracuda Networks recommends turning off all spam controls on
your mail server in order to eliminate potential conflicts." This Solution is aimed at helping customers disable
those settings on an Exchange Mail server.
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