• Geographically Diverse Filtering Zones
• TLS Support
• What is the maximum attachment size for email?
• Setting Destination Server, Priority and Ports - Multiple Inbound Delivery Ports Supported
• Email Filter Rule Examples
• type=AAAA: Host not found
• What headers are added to the mail messages?
• 452 4.3.1 Insufficient system resources
• What to do if your filters don't work
• Spam Filtering Levels