Microsoft is investigating an ongoing Exchange Online issue that began on February 5, where a new URL rule is incorrectly flagging legitimate emails as phishing and quarantining them, blocking some users from sending or receiving messages. The company is reviewing and releasing quarantined messages while working to unblock affected URLs and confirm full remediation. #Microsoft #ExchangeOnline
Keypoints
- An Exchange Online bug is mistakenly marking legitimate email messages as phish and quarantining them.
- The incident began on February 5 and is preventing some customers from sending or receiving emails.
- Microsoft traced the problem to an updated URL rule that incorrectly flags certain URLs as malicious.
- The company is releasing quarantined messages for affected users and working to unblock legitimate URLs.
- Microsoft has experienced similar anti-spam and machine-learning related email quarantine issues in the past.