Microsoft confirms September 2026 Windows updates can break File History, stop new backups, and trigger “Reconnect your drive” warnings.

[File History (known issue)] Fixed: This update addresses an issue where File History might fail to back up or restore files to an external drive or network location. Affected devices might ...

A bug in the Windows Sept patch Tuesday update may stop File History from working. But a new optional update fixes it.

Microsoft has fixed a known issue that breaks the built-in File History backup feature on some Windows systems after installing the September 2026 security updates. In a Saturday service alert seen by ...