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‘Quarantined email’ notifications: what you need to know

29 June 2021

If you have migrated to the online Exchange environment, you may receive a notification that an email sent to you has been placed in quarantine. The notification will be sent by: quarantine@messaging.microsoft.com.  

What should you do if I receive a notification email from Microsoft about a quarantined email?

If you receive such a notification, don’t worry: it’s a security measure. The notification comes from Microsoft, and the suspicious mail has been placed in a safe environment where you can review it safely. The mail may be spam or could be dangerous (phishing mail).

How do you safely review the suspicious mail?

The Microsoft notification is safe to open. It contains the following information:

  • Sender: The name of the sender and email address of the quarantined message.
  • Subject: The subject of the quarantined message.
  • Date: The date and time (in UTC) that the message was quarantined.

You can then choose one of the following actions:

  • Block sender: This will add the sender of the email to your blocked senders list.
  • Release: If the message isn’t spam, you can send the mail to your mailbox. You don’t need to go to the safe environment to do this (this option is not available if the mail is a phishing mail).
  • Review: Click on the ‘review’ link to review your message in a safe environment. This will take you to the Security & Compliance Center in your browser where (depending on why the message was quarantined) you can review, release, delete or report your quarantined messages.   

If you have quarantined emails, you will receive a Microsoft notification every three days. Messages will be held in quarantine for 30 days. After this they will be deleted.

You can also manually check your quarantined messages. To find out how read knowledge item 3087 in the helpdesk portal.

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