Over the weekend, several reports had suggested that some Windows 10 20H2 devices were experiencing problems after installing the latest KB4592438 delivered earlier in December. The issue was with the Check Desk tool that was causing booting to fail on some Windows 10 devices.
In the support document of KB4592438, Microsoft has now acknowledged the Windows 10 chkdsk problem:
A small number of devices that have installed this update have reported that when running chkdsk /f, their file system might get damaged and the device might not boot.
The Windows maker added that the issue is now resolved and "should now be prevented automatically on non-managed devices." The company said that restarting your device might help with the resolution to apply faster on your device.
Please note that it can take up to 24 hours for the resolution to propagate to non-managed devices. Restarting your device might help the resolution apply to your device faster. For enterprise-managed devices that have installed this update and encountered this issue, it can be resolved by installing and configuring a special Group Policy.
Microsoft has also shared the following workaround for devices that have already encountered this issue and are unable to start up:
- The device should automatically start up into the Recovery Console after failing to start up a few times.
- Select Advanced options.
- Select Command Prompt from the list of actions.
- Once Command Prompt opens, type: chkdsk /f
- Allow chkdsk to complete the scan, this can take a little while. Once it has completed, type: exit
- The device should now start up as expected. If it restarts into Recovery Console, select Exit and continue to Windows 10. Note: After completing these steps, the device might automatically run chkdsk again on restart. It should start up as expected once it has completed.
Microsoft hasn't shared which versions are affected by this Windows 10 chkdsk bug, but the two latest versions do appear to be impacted by this problem. For more details, head over to KB4586853 for Windows 10 May 2020 Update (version 2004) or KB4592438 for version 20H2.