An Ongoing Technical Challenge

Microsoft has issued a formal warning regarding its latest software releases, noting that the built-in [File History](https://www.bleepingcomputer.com/news/microsoft/how-to-use-windows-10-file-history-to-make-secure-backups/) backup feature may malfunction following the installation of September 2026 security updates. This feature, which has been a staple for data protection since its introduction in Windows 8, is designed to automatically create recovery copies of documents, music, pictures, videos, and desktop files.

The problem was first brought to light by Microsoft MVP Susan Bradley and later documented in a formal [service alert](https://admin.cloud.microsoft/Adminportal/Home?source=applauncher#/windowsreleasehealth/:/issue/WI1474330). According to the company, the issue manifests as an inability to initiate new backups or update existing ones, which can disrupt established data preservation workflows for both home and enterprise users.

Symptoms of the Backup Failure

Users experiencing this glitch may notice several specific system behaviors. When attempting to run the backup process, the application often crashes, with error logs in the Windows Event Viewer pointing toward FileHistory.exe and KERNELBASE.dll as the primary points of failure.

Beyond explicit crashes, the user interface may provide misleading information. Many users report that Windows incorrectly triggers 'Reconnect your drive' alerts, despite the external storage devices or network-attached storage (NAS) locations being fully operational. Furthermore, timestamps for the 'Last Backup' fail to refresh, and users attempting to restore files may find that no previous versions are available, rendering the recovery aspect of the feature unusable.

A Difficult Update Cycle

The issues surrounding File History follow a challenging month for Microsoft's cumulative update delivery. The September 2026 security updates have been linked to a variety of widespread problems across the Windows ecosystem. Earlier this month, the company was forced to address [Remote Desktop Services failures](https://www.bleepingcomputer.com/news/microsoft/microsoft-september-updates-cause-rds-failures-on-windows-server/) that impacted enterprise environments, as well as distinct [Hyper-V issues](https://learn.microsoft.com/en-us/windows/release-health/status-windows-11-26h1#host-folder-shares-might-be-unavailable-in-hyper-v-based-linux-vms) that affected folder sharing in virtualized Linux environments.

While Microsoft quickly [released out-of-band updates](https://www.bleepingcomputer.com/news/microsoft/microsoft-releases-emergency-windows-updates-to-fix-rds-failures/) to mitigate the most critical infrastructure bugs, the remediation process remains incomplete. The company has publicly confirmed that these emergency patches did not resolve every issue, particularly regarding [USB audio problems](https://www.bleepingcomputer.com/news/microsoft/microsoft-september-updates-break-audio-on-some-windows-pcs/) that continue to persist for some users.

Moving Forward

For other bugs introduced this month, such as authentication errors preventing domain logins, Microsoft has [shared a temporary workaround](https://www.bleepingcomputer.com/news/microsoft/microsoft-releases-workaround-for-windows-domain-login-authentication-issues/) while a permanent fix is developed. However, as of now, the company has not provided a specific timeline for when the File History backup issue will be addressed through a formal update.

As the situation evolves, users who rely on the built-in backup utility are advised to monitor the official Windows release health dashboard. Given the importance of data retention, those with critical files may need to consider third-party backup solutions until Microsoft issues a patch that restores full functionality to File History.

Sources

• BleepingComputerMicrosoft: September updates break File History backup feature