Email Quarantine: How to Review Blocked Messages

Email Quarantine: How to Review Blocked Messages

Your organization's email security filter automatically quarantines messages that appear to be spam, phishing, or contain suspicious content. Occasionally, a legitimate email may be caught by these filters. You can review your quarantined messages and release legitimate ones.

How to Check Your Quarantine

  1. Go to the Microsoft 365 Defender quarantine portal at security.microsoft.com/quarantine.
  2. Sign in with your work email and complete MFA.
  3. You will see a list of quarantined messages addressed to you, including the sender, subject, and reason for quarantine.
  4. Click on a message to preview it. Review the sender address and content carefully before taking action.
  5. If the message is legitimate, click Release message to deliver it to your inbox. If it is spam or suspicious, leave it in quarantine or delete it.

Quarantine Notifications

Depending on your organization's settings, you may receive periodic quarantine notification emails listing recently quarantined messages. These notifications include direct links to release or review each message. If you do not receive these notifications and would like to, contact CMO IT Services.

Important Caution

If you are unsure whether a quarantined message is safe, do not release it. Instead, submit a ticket and ask CMO IT Services to review it. Releasing a phishing email from quarantine bypasses the filter and delivers the threat to your inbox.

Need help? Submit a ticket and a CMO IT Services technician will assist you.

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