October Windows Server updates may disrupt Exchange email. Learn which servers are affected, the symptoms, and Microsoft's registry workaround.

Microsoft has acknowledged that the October 2026 Windows Server updates may be destabilizing Exchange Server. The problems are related to this list of Windows Server updates (see here) and Microsoft ...

Microsoft has confirmed that this month's Windows Server security updates are causing OWA sign-in and mail delivery issues on some Exchange Server systems.

Exchange servers go down after Windows Server’s October updates. Microsoft is investigating the issue.

Microsoft warns that the October 2026 Windows Server updates may destabilize on-premises Exchange servers. OWA (Outlook on the Web) logins fail, and mail ...

Microsoft is ending support for Exchange Server 2016, Exchange Server 2019, and Outlook 2016 on October 14, 2025. That date might seem far off, but if you’re managing email systems or Office ...

Microsoft this week announced it will be bringing its Extended Security Update (ESU) program for on-premises Exchange Server 2016 and 2019, offering organizations critical protection as they approach ...