Technical Tip: How to allow empty 'Envelope From' emails such as automatic reply/Out of office replies to be relay to external recipient

1. Automatic reply/ Out of office email was not able to relay over FortiMail because the From column was empty.

2. Mail server receives error 'reject=554 5.7.1 Relaying denied'.
3. Navigate under Policy -> Access Control -> Receiving.
4. Select the 'New+' button and set the sender to wild card '*' and Recipient to 'External'.

5. Specify the source to be a specific mail server IP to avoid open relay from FortiMail.
6. Set the action to 'Safe & Relay'.
   

Note:

If multiple IPs are required for the relay, choose 'IP group' instead of 'IP/Netmask' as a source: