Microsoft Acknowledges High CPU Utilization Bug in Windows 11 File Explorer

Windows 11
(Image credit: Tom's Hardware)

If you’re experiencing sudden high CPU utilization in Windows 11, Microsoft might know what’s causing your problems. According to the Redmond, Washington-based software giant, a nasty bug in File Explorer affects Windows 11 21H2 and 22H2. 

Specifically, Microsoft says that users are prevented from viewing the “Effective Access” menu in the “Advanced Security Settings” dialog box for shared files/folders. Instead of properly responding to the user’s command, “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.”

Microsoft reports that the high CPU utilization will continue to plague the Windows 11 system until the currently logged-in user signs out or until the system is rebooted. Simply locking Windows will not resolve the bug, according to Microsoft. 

It should be noted that this File Explorer bug was introduced with KB5026368 and KB5026372 for Windows 11 21H2 and 22H2, respectively. These were Patch Tuesday Cumulative Updates released on May 9. What’s interesting is that it took well over a month for Microsoft to acknowledge the issues; however, the following statement from the company seems to explain this seemingly slow response time.

“This issue is unlikely to be experienced by consumers using Windows devices in their home,” which is understandable given that Effective Access is geared more towards specific corporate environments. 

If you are currently experiencing high CPU utilization when accessing this specific feature, you can attempt Microsoft’s suggested logout/reboot workarounds. In the meantime, the company says it is currently working internally on a fix, which should be available later this month.

Brandon Hill

Brandon Hill is a senior editor at Tom's Hardware. He has written about PC and Mac tech since the late 1990s with bylines at AnandTech, DailyTech, and Hot Hardware. When he is not consuming copious amounts of tech news, he can be found enjoying the NC mountains or the beach with his wife and two sons.

  • Nick_C
    "The big affects Windows 11 21H2 and 22H2"
    Reply
  • Amdlova
    With 12700t see some five watts changing windows 11 to windows 10.
    Microbug 11 have more things eating cpu than windows 10
    Reply
  • animadversor
    Why not just kill and restart explorer.exe? That at least seemed to fix the problem for me.
    Reply
  • Rabohinf
    Is 11 still in beta?
    Reply
  • Sleepy_Hollowed
    Rabohinf said:
    Is 11 still in beta?
    All software is alpha or beta when it’s using AGILE, so yes, basically all of it.
    Reply
  • InvalidError
    I miss the old days where a File Explorer was just a dumb file explorer that didn't have a heap of background processes to worry about. Where copying or moving a folder started the actual operation immediately instead of sometimes taking minutes of "calculating" before starting.
    Reply
  • cristovao
    Admin said:
    Microsoft says that the File Explorer bug can cause high CPU utilization that requires logging off or rebooting the machine.

    Microsoft Acknowledges High CPU Utilization Bug in Windows 11 File Explorer : Read more
    It's just Chat Gpt procuring files and information.
    Reply
  • purpleduggy
    so i wasn't just imagining it...
    Reply
  • Sippincider
    Wonder if this is what's affecting my POS workplace PC, which sits at full fans with just Outlook open.

    Told our IT department something is not right and to see what all's running. Their response was full fans while doing nothing is normal operation... :rolleyes:
    Reply
  • InvalidError said:
    I miss the old days where a File Explorer was just a dumb file explorer that didn't have a heap of background processes to worry about. Where copying or moving a folder started the actual operation immediately instead of sometimes taking minutes of "calculating" before starting.
    I still prefer total commander
    Reply