This solution applies to all Email Security Gateway configured to use Global Quarantine.
If you notice a Delivery Detail in your Message Log stating ?250 2.6.0 Ok, duplicate quarantine message discarded,? this indicates you have received a duplicate message to multiple recipients and only one copy has been kept. This is intended behavior and occurs to save space and processing time.
This will occur if you have Global Quarantine enabled. You can check this setting in Basic > Quarantine. If you have the Global radio button selected (Quarantine Type header) and you have a Quarantine Delivery Address entered (Global Quarantine Configuration header), then you are using Global Quarantine. In addition to the above, you must have your Quarantine score (found in Basic > Spam Scoring) at an appropriate level to send anything to Global Quarantine.
The Email Security Gateway will list messages with multiple recipients as separate emails in the Message Log. Only the first message will be delivered to the Global Quarantine address. The rest will be marked as duplicate messages and discarded. You can then decide if you would like to distribute the message to the intended recipients.
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