Windows 10: Explorer.exe high CPU and also other weird symptoms

I recently had a some kind of permissions problem where lots (10s or 100s) of random files were given wrong permissions for some reason. So my Windows 10 (1909) was quite crippled. But then I ran Tweaking.com Windows Repair with (almost) full settings and it seemingly repaired everything. However, now I'm experiencing two other problems which may or may not be related:

Explorer.exe randomly causes very high CPU usage. Using Process Hacker, it's specifically usually ""ntdll.dll!rtinitializeresource" that is doing the CPU hogging. I have no idea what that is about.

Other problem is Firefox started crashing. It only works for 10 seconds, then a complete freeze. Then, looking at Task Manager, the firefox.exe causing the problem is "Suspended". Nothing else can be done except ending that task. But I can't do anything with Firefox. An interesting clue is that I have also Firefox Portable installed and that works, doesn't crash. But normal Firefox freezes almost immediately.

Any idea what might be going on and how to fix?

I'm running Bitdefender Total Security so I shouldn't have any viruses.

:)

 

Windows Explorer high CPU Usage in Windows 10

To further troubleshoot the issue, we suggest checking the Task Manager again to see what are the
applications that have high CPU usage. To do this, follow the same steps you did from the previous reply:

• Click on the Start button and type Task Manager on the search box.
• On the Task Manager window, you should see the programs running.
• Click on the More details drop-down button to see the total number of apps running and their real-time CPU usage.

However, based on your response above, it seems that you may need to create a new user account again and just install your apps manually instead of copying them as your
previous user account might be corrupted.

Once your done with the steps, please let us know how it goes.

 

Windows Explorer high CPU Usage in Windows 10

Hi Andrew,

Usually, too many background processes can boost your CPU usage. Since you already disabled the apps that are not necessary on startup,
we suggest checking the applications running once you have successfully boot Windows 10. To do this, simply follow the steps below:

• Click on the Start button and type Task Manager on the search box.
• On the Task Manager window, you should see the programs running.
• Click on the More details drop-down button to see the total number of apps running and their real-time CPU usage.

From there, you should see what applications are running on high CPU usage. You can also
restart the Windows Management Instrumentation service and see if your CPU performance will improve. Follow the instructions below to restart the service:

• Click on the Start button and type Services.
• Scroll down the list and look for Windows Management Instrumentation.
• Right click on it and select Restart.

Should you have further questions, please let us know.

 

Windows Explorer high CPU usage as Apps or Background Process...

3May2018...

Running Windows10 Home Ver 1709 latest OS Build on

Intel Core i5 CPU @ 3.8GHz.

Recently Windows Explorer has been running at high CPU usage 45% to 50%

Even when I am not using File Explorer - Windows Explorer runs as a Background Process as same high CPU usage...

First when will Microsoft stick to the new name File Explorer - instead of showing Windows Explorer as the app in the Task Manager...confusing :-(

Two - I saw someone else with the same problem and a ridiculous multi step cumbersome solution of creating another account (where Windows Explorer did not have high CPU) and then a painful exercise of trying to migrate all applications and files from one
account to the other.

Apparently the original user account may have had a corruption....

Are there any simpler explanations out there on how to fix run away Windows(File) Explorer???