Windows 11 File Explorer bug confirmed by Microsoft — here's what happens next

Windows 11 File Explorer Hero
(Image credit: Windows Central)

What you need to know

  • A Windows 11 bug can cause high CPU usage when using the Effective Access feature.
  • Restarting your device or signing out the affected user may mitigate the issue.
  • Microsoft is working on a permanent fix for the bug.

Some Windows 11 users may see a spike in CPU usage due to a recently discovered bug in File Explorer. The problem can increase CPU usage when someone tries to use the Effective Access feature. Microsoft has confirmed the bug and is working on a permanent solution that should roll out this month. In the meantime, there is a workaround for the issue.

The problem first appeared in the KB5026368 and KB5026372 updates for Windows 11 version 21H2 and 21H2, respectively.

Microsoft's website explains the bug:

"After installing updates released on May 9, 2023 or later updates, you might be unable to view Effective Access in the "Advanced Security Settings" dialog for shared files or folders. On affected devices, when the "View effective access" button is selected, you will receive the message "Computing effective access...." but the results of the query might not be displayed and explorer.exe might continue to use CPU after the Advanced Security settings dialog is closed. This issue is unlikely to be experienced by consumers using Windows devices in their home. "

Effective Access is a feature rarely used by general consumers, so it's unlikely that you've run into this bug. But if you have, there is a workaround for it.

"If you have attempted to view effective access, you can mitigate the CPU usage issue by restarting your device or by signing out for the affected user," explained Microsoft.  "Note: Locking Windows will not mitigate this issue, you must sign out."

In other File Explorer-related news, Microsoft recently decided to keep a group of legacy features in the app that were going to be removed. The company was going to remove a group of options due to low usage but backtracked on the change before rolling it out to general users.

Sean Endicott
News Writer and apps editor

Sean Endicott brings nearly a decade of experience covering Microsoft and Windows news to Windows Central. He joined our team in 2017 as an app reviewer and now heads up our day-to-day news coverage. If you have a news tip or an app to review, hit him up at