We're using our C150 to quarantine emails that arrive with some form of encryption (e.g. a password-protected .zip). When a matching email first arrives, it's correctly quarantined and sends an "Encrypted message detected" notification to the relevant recipient, as expected. However, after releasing the email to the recipient, another "Encrypted message detected" notification is sent related to the same email, even though the recipient receives the released version too. It's causing some people a bit of confusion to get this second notification at the same time they get the email it's complaining about.
We have the following setup under Mail Policies:Anti-Virus -> Anti-Virus Settings -> Encrypted Messages:
Action applied to message = Quarantine
Archive original message = No
Modify message subject = Prepend the text "[WARNING : MESSAGE ENCRYPTED]" (Interestingly, the first notification generated doesn't include this prepended text as part of the subject, but the second one does; not sure if this is a clue to what's happening)
Add custom header to message = No
Container notification = System Generated
Other Notification = Recipient + Others (admins)
Modify message recipient = No
Send message to alternate destination host = No
If anyone can shed some light on why this is happening or if you've seen it before, please let me know.