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Microsoft Acknowledges Exchange Online Spam Filter Mistakenly Blocks Valid Email - gbhackers.com

Microsoft Outlook February 10, 2026 high impact

Microsoft Acknowledges Exchange Online Spam Filter Mistakenly Blocks Valid Email Microsoft has acknowledged a significant issue with its Exchange Online spam filter that is incorrectly blocking legitimate emails from reaching users' inboxes. This filtering error represents a critical deliverability problem affecting organizations relying on Microsoft 365 for email communications. The issue highlights the challenges email service providers face in balancing spam protection with ensuring valid messages reach their intended recipients. Organizations using Exchange Online may experience reduced email delivery rates and customer communication failures due to false positives in the spam filtering system. Microsoft's acknowledgment suggests the company is working on a resolution to improve filter accuracy.

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EUM / SES Relevance

Directly relevant to AWS SES as a competing email delivery platform. This Microsoft Exchange Online deliverability issue demonstrates the importance of accurate spam filtering and sender reputation management—core competencies of SES that help ensure legitimate emails reach inboxes while maintaining security.

Key Takeaways

  • arrow_right_alt Exchange Online's spam filter is incorrectly blocking legitimate emails, causing deliverability issues for organizations
  • arrow_right_alt The false positive problem affects email reach and customer communications for Microsoft 365 users
  • arrow_right_alt This represents a critical sender reputation and inbox placement challenge for enterprises
  • arrow_right_alt Microsoft has acknowledged the issue and is working toward a resolution