Spoofing messages often have envelope senders (specified by the envelope field "MAIL FROM") set to blank to evade sender verification. Trend Micro Email Security allows you to scan messages for empty envelope senders to help you combat spoofing.
  • Some normal messages may also have empty envelope senders, such as bounce messages or notification messages. Selecting this criteria will affect these messages.
  • This criteria is available for inbound protection only.


  1. On the Scanning Criteria tab, click Advanced.
  2. Select Envelope sender is blank.