Microsoft has resolved a bug that stopped File History from backing up or restoring files to external drives or network locations after the September 2026 security update. The fix ships in the optional cumulative updates KB5124006 and KB5124010 for Windows 11 26H1 and 24H2/25H2 respectively. Affected users had seen crash events referencing FileHistory.exe, false 'Reconnect your drive' prompts, and backups that stopped updating.
bleepingcomputer.com
· 2026-09-24
Microsoft confirmed that its September 8 Patch Tuesday update broke File History backups on Windows 11 (23H2 through 26H1) and Windows 10 ESU devices, causing errors like false 'reconnect drive' prompts and missing previous file versions. The company has released an optional preview update to fix the issue, though it currently does not apply to Windows 11 23H2 or Windows 10.
zdnet.com
· 2026-09-23
Microsoft has acknowledged that its September 2026 security updates cause the legacy File History backup tool to fail on multiple Windows 10 and 11 versions. Affected PCs may show FileHistory.exe crashes in Event Viewer, false 'Reconnect your drive' warnings, and backups that stop updating even though the external or network drive is connected properly.
bleepingcomputer.com
· 2026-09-21
GoKawiil