How do I access quarantined messages in a shared mailbox
To access and review quarantined messages of a shared mailbox, follow these steps:
1. Visit https://security.microsoft.com/quarantine
2. If you're not already logged in, log in using your own account
3. Click on the filter icon
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4. Type the shared mailbox email address in the Recipient address
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5. Click Apply
You should now see any quarantined messages in the shared mailbox account.
Important: Please use caution when reviewing a releasing quarantined messages. Many quarantined messages were sent there because they were detected as potentially malicious.