File Explorer and Microsoft app login has stopped working after latest Windows Update (bug only on Lenovo Legion)

Try this

1. Access the registry using "regedit"
2. Go to the location: HKLM \SYSTEM\CurrentControlSet
3. Locate the key "Control" (This is the main issue)
4. Right click the key "Control" and got to "Permissions", than click "Advanced" and you will notice it's inheritance has been broken because it will give you the option to "Enable Inheritance". Click "Enable Inheritance"
5. One Enable Enheritance is clicked on the "Control" key that should also fix all the permissions below it for all subsequent keys.
6. Reboot for good measure to ensure the settings stick between reboots.

I found a solution, maybe two.

First: if someone has a WD hard drive in Lenovo Legion > LINK

Second: if updating the disk firmware does not help and no additional windows updates appear, you must manually download the 24H2 ISO from the Microsoft website and install it while preserving data and applications > LINK

I think the problem was that the update download was blocked and some parts of the 24H2 update were missing. Maybe it's the hard drive firmware or something else.

I really appreciate you trying all those steps already I know how frustrating it is when none of the usual fixes resolve the issue. Since this seems specific to Lenovo Legion devices after that Windows Defender update, and standard rollback and repair methods haven’t helped, here’s what I suggest next:

1. Block Reinstallation of the Problematic Update

Even after rollback, Windows may auto-reinstall the update:

Download the Show or Hide Updates Troubleshooter tool from Microsoft (wushowhide.diagcab)

→ This lets you hide KB2267602 or KB890830 so they won't reinstall.

(Let me know if you need the direct link or step-by-step.)

2. Clean Boot + Custom Update Hold

Boot with all non-Microsoft services disabled, then run:

DISM /Online /Cleanup-Image /StartComponentCleanup /ResetBase

This resets update history and may avoid triggering the bug.

3.3. Advanced Fix – Disable Defender Cloud Protection (Temporary)

Some have had success with:

Set-MpPreference -MAPSReporting Disabled
Set-MpPreference -SubmitSamplesConsent 2

You can run these in PowerShell (Admin) it reduces Defender’s real-time interactions that may conflict with Lenovo software.

If this still doesn’t help, I can walk you through submitting logs to Microsoft Feedback Hub tagged specifically to this Lenovo + Defender interaction that’s helped similar cases get attention from the engineering team.

Let me know how you’d like to proceed I’ll stay with you through this.

Warmly,

Cherrelyn

All your steps have already been done before, none of this helps :(

Hi, I’m Cherrelyn, an Independent Advisor. I hear how disruptive this is, especially when it impacts both File Explorer and essential apps like Excel or OneDrive thank you for sharing the detailed info. Since this issue only appears on Lenovo Legion devices after recent updates (KB2267602 or related Defender/intel fixes), and a restore only works temporarily, this does seem linked to a conflict between the update and Lenovo-specific software or drivers.

Here are some suggestions to help stabilize your system:

1. Temporarily Pause Windows Updates

-Go to Settings > Windows Update > Pause updates for 1–2 weeks to avoid reapplying the same problematic patches.

2. Uninstall the Conflicting Update

-Open Settings > Windows Update > Update History > Uninstall Updates.

-Look for KB2267602, KB890830, or similar.

-Restart after uninstalling.

3. Run SFC and DISM

To repair system files:

sfc /scannow
DISM /Online /Cleanup-Image /RestoreHealth

4. Update Lenovo Drivers/Firmware

-Use Lenovo Vantage or visit Lenovo Support to:

-Install any BIOS, chipset, or storage driver updates.

-Make sure Lenovo System Interface Foundation and Lenovo Service Bridge are updated.

5. Create a New Local Admin Account

If the Microsoft login is blocked:

-Use Settings > Accounts > Add another user (local)

-Log into that profile to test File Explorer stability.

Let me know if you’d like help running these steps or rolling back specific patches safely. You're not alone several users are seeing this and we’ll work through it.

Warm regards,

Cherrelyn