on your Windows 11 computer File History not working or if you see the “Reconnect your drive” warning even though your external disk is connected, the problem may not be caused by the disk you are using. Microsoft has confirmed that the September 2026 security update broke the File History feature on some Windows 11 computers. Computers affected by the issue cannot create new backups or update existing backups. Fortunately, Microsoft has also released the fix. In this guide, you can first check whether your computer is affected by the issue in question, and then follow the necessary steps to run File History again.
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Check if you are facing Windows 11 File History issue
According to Microsoft’s statement, the problem is caused by the September 2026 Windows security update. KB5124008 It may appear after installation. File History normally regularly saves different versions of your personal files to an external drive or network location. This way, you can go back to an older copy of a file that you accidentally deleted or changed.
When the problem occurs, Windows crashes even if a properly working compatible backup disk is connected to the computer. “Reconnect your drive” It can show the warning. In addition, the Last Backup information may not be updated. You may also encounter the message “There is no previous version” for files you have previously backed up. Microsoft also states that application crash records related to FileHistory.exe and KERNELBASE.dll may be visible in the Event Viewer on some computers.
Image 1 here: Control Panel > System and Security > File History screen. If possible, view the image from your own Windows 11 test computer. at least 1280 pixels widepreferably 1600 × 900 pixels. If you can catch the “Reconnect your drive” error, this screenshot has higher editorial value.
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Check for Windows 11 update
Microsoft fixes File History issue Fixed in Windows updates released on or after September 22, 2026 says. The KB5124010 update released for Windows 11 24H2 and 25H2 also includes the fix in question. Microsoft’s release notes clearly state that an issue where File History was unable to backup and restore to an external drive or network location has been fixed.
on your computer Settings > Windows Update follow your path and Check for updates Click . If you see a new Windows update available, download and install it. If Windows asks you to restart after the installation is complete, save your open documents and restart the computer. Microsoft recommends installing the latest Windows update available for your device rather than just searching for a specific package.
Image 2 here: “Check for updates” section on the Windows Update screen. screenshot 1600 × 900 pixels you can prepare. If KB5124010 appears, including the update name in the frame makes it easier for the reader from the search result to follow the steps.
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See if the KB5124010 update is installed
It will be useful to check the installation history after updating via Windows Update. Settings > Windows Update > Update history You can see recently installed updates by entering the section. If you are using Windows 11 24H2 or 25H2, you can look for the KB5124010 package here.
The File History fix is included directly in Microsoft’s release notes for KB5124010 dated September 22. The update covers operating system builds 26100.9550 for Windows 11 24H2 and 26200.9550 for Windows 11 25H2. The same package is also offered on the 26H2 side with compilation 26300.9550.
Image 3 here: Windows 11 Update history screen. You can crop the screenshot to show the KB number, but not the width of the source image. at least 1280 pixels tobacco.
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Re-run File History
After installing the update and restarting the computer Control Panel > System and Security > File History Follow your path. Make sure your external disk is connected. If you are backing up to a network location, you can re-select that network location in File History.
Windows can normally start the process itself during the next scheduled backup. Instead, if you want to immediately check if the fix worked, click on the File History screen. run now You can use the option. Microsoft also recommends this method to initiate a manual backup after reconnection.
Image 4 here: Screenshot showing the “Run now” option on the File History screen. You can also choose 1600 × 900 pixels here.
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If the “Reconnect your drive” warning persists, check the disk
If the warning continues despite installing the latest Windows update, this time it is necessary to check whether there is a real connection problem. Disconnect and reconnect the external disk you are using via USB and see if the drive appears in File Explorer. Then go back to the File History section.
If you are backing up over a network Control Panel > System and Security > File History Reselect the network location from the section. Microsoft’s recommended troubleshooting method for the normal “Reconnect your drive” error also includes these steps. This way you can distinguish between an update error and a truly disconnected backup drive.
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Verify Windows 11 File History is working again
Don’t just rely on the error message disappearing once File History starts working again. Check that the Last Backup time has changed after running a new backup. You can then try to access older versions of one of the files you backed up.
File History can automatically back up files in libraries such as Documents, Pictures, Videos and Music. You can also add folders in other locations to the scope of protection by adding them to an existing library. Microsoft notes that File History can use a network location as a backup destination in addition to an external drive.
Image 5 here: File History main screen after successful backup. Frame the section where the last backup date and time is visible. 1600 × 900 pixels source screenshot would be appropriate.
Is it necessary to uninstall the update for Windows 11 File History problem?
Microsoft’s current solution is not to uninstall the update, Installing a current Windows package released on or after September 22, 2026. Therefore, before trying to uninstall KB5124008, it would be better to check the latest update available for your device via Windows Update.
Frequently Asked Questions
Why does Windows 11 give a “Reconnect your drive” warning?
The KB5124008 update dated September 2026 may cause File History on some computers to incorrectly detect a connected and working drive as disconnected. Microsoft confirmed this issue and fixed it in subsequent updates.
Which Windows 11 update solves the File History issue?
Microsoft states that the problem has been fixed in updates released on September 22, 2026 and later. KB5124010, released for Windows 11 24H2 and 25H2, includes the File History fix.
If I see an error even though an external disk is connected, is the disk damaged?
Not necessary. The problem caused by KB5124008 can cause Windows to show the “Reconnect your drive” message even though a working backup drive is connected. First update Windows, then check the connection of the external disk if the problem persists.
How do I launch File History manually?
Go to Control Panel > System and Security > File History. With your backup drive connected, you can start the new backup using the Run now option.