As per usual, Microsoft is breaking quite a few things with new security updates for Windows 11. This time, it is the turn of File History and Always On VPN connections.
The September 2026 Windows 11 security update brings a lot of problems with it again. Users may experience issues with File History where files are no longer automatically backed up, and incorrect notifications appear. Always On VPN connections are also affected, although Microsoft has a temporary solution ready.
The fact that problems are cropping up with Windows security updates is nothing new by now. Previously, an update broke the desktop background, and blocked Teams and Outlook on ARM-based devices.
File History
Microsoft’s File History automatically saves copies so that deleted files can be restored using an older version from hours or days ago. This way, you don’t immediately lose accidentally deleted files. However, have you installed the September 2026 security update? Then you had better take extra care to save your files properly.
Microsoft warned that the built-in File History backup feature in Windows may no longer work on certain systems after installing the September 2026 security updates.
“After installing the September 2026 Windows security update, some customers using File History might be unable to back up or update backups,” according to the report, reviewed by Bleeping Computer. “File History, available via Control Panel > System and Security > File History, is used to back up files to an external drive or network location.”
Furthermore, affected devices receive incorrect notifications such as “reconnect your drive” when it is actually correctly connected, or “Last backup” not being updated. The affected Windows releases are Windows 10 21H2 or later, Windows 10 Enterprise LTSC 2016/2019, and Windows 11 23H2 and later.
Always On VPN
In addition to File History, the September update also breaks the Always On VPN connection, which replaces the old DirectAccess technology. Always On VPN is a feature that allows Windows devices to automatically establish a secure VPN connection to the corporate network without user intervention. As the name suggests: the connection is essentially always on. As soon as a device has an internet connection, the tunnel to the corporate infrastructure is automatically established.
Microsoft is now warning that customers may experience issues when their systems try to connect to the corporate network via Always On VPN, as noted by Bleeping Computer. “Affected VPN connections might stay in a ‘Connecting’ state or repeatedly try to connect without success. Subsequent connection attempts might also show the error message: ‘The specified port is already in use.'” The affected systems are Windows 11 Version 26H1, 25H2, and 24H2.
Microsoft is currently looking for a solution but is offering a temporary workaround for affected customers. “IT administrators can mitigate this issue by changing the Always On VPN profile from automatic protocol selection to a single protocol, either SSTP only or IKEv2 only, depending on their environment and configuration.”