Windows XP 'explorer.exe' taking up 100% of my CPU time

[Chaotic42]

There's a system here at work that will often have explorer.exe go nuts and run up to 100% CPU usage, sending the computer into fits. I've looked on line and everyone seems to have their one magic solution that will always work, then it never seems to work for anyone else.

Has anyone run into this? If so, do you have any ideas about how to fix it? The OS has been reinstalled before with no luck.

 

[Raduque]

The last time I saw this issue was with my sister's laptop. She had gotten a virus that was causing explorer.exe to send a hundred million spam emails a minute. I had to do a restore because nothing would clean it (though blocking port 25 on my router stopped the spam flow from killing my internet connection).

 

[tvdang7]

yep same as my GF's laptop.

 

[RebateMonger]

Explorer.exe is a very important process in Windows. If you've re-installed the OS and are having problems, then it might be a low-level problem in the PC.

I'd start with the basics and confirm that the hard drive, memory, CPU, etc. are functioning properly. Any of those can mess up the hard drive or the Registry and cause recurring problems in Windows. Run overnight tests of each of those components.

And, yeah, it could also be a mail worm or some such invader.

 

[VirtualLarry]

It could be a corrupted media file or zip file.

 

[Chaotic42]

Originally posted by: RebateMonger
Explorer.exe is a very important process in Windows. If you've re-installed the OS and are having problems, then it might be a low-level problem in the PC.

I'd start with the basics and confirm that the hard drive, memory, CPU, etc. are functioning properly. Any of those can mess up the hard drive or the Registry and cause recurring problems in Windows. Run overnight tests of each of those components.

And, yeah, it could also be a mail worm or some such invader.

Our IT department would probably just replace it before they did all of that. I'm not IT, but I defrag and scan our computers regularly because they don't.

 

[RebateMonger]

Originally posted by: Chaotic42
Our IT department would probably just replace it before they did all of that. I'm not IT, but I defrag and scan our computers regularly because they don't.

It doesn't really cost much to run those tests. You stick a CD into the PC when you leave for home and let it run overnight. In the morning, remove the CD and reboot the PC.

 

[htne]

This happened to me about 3 or 4 years ago. Basically, the computer ran fine, and would run pretty much any application, as long as I started it from a desktop icon or the Start menu. If I clicked on "My Computer", and started Windows File Explorer, then the cpu usage would immediately go to 100% and stay there. I could (slowly) do a Ctrl-Alt-Del and kill explorer.exe and then restart it. The system would then be stable until I started Windows File Explorer again. The same thing would happen if I started Control Panel.

I NEVER did figure it out. After several hours of searching, I gave up and did a clean install of XP -- problem solved.

At the time, I was running Kaspersky anti-virus, with the latest virus definitions. I even did a full scan and found nothing. So I don't think it was malware, just something screwy in Windows.

 

[Schadenfroh]

Checkout this part of John's Malware Removal Guide

* Make a new folder called McAfee in the root of the c:\ drive of the computer you're going to scan.
* Download the win_betaengdat.zipand extract the contents of the file into C:\McAfee
* Download and save this batch file to c:\McAfee since it is responsible for launching the command-line scanner with all of its options enabled, including heuristics and adware/spyware options. You can run scan.exe /? to get a list of available options.
* I usually recommend starting the system in Safe Mode with Command Prompt (so explorer.exe doesn't run) and then running the command c:\McAfee\RUNSCAN.bat to launch the scanner. It'll run in normal mode too, but if malware has multiple processes that watch each others' backs, and they're running, then they'll just repair each other up after the scanner kills them off.
* When the scan is done, it will put a report.html file in c:\ showing what it found.

To see if window's files are corrupt, use SFC

sfc /scannow

This command will immediately initiate the Windows File Protection service to scan all protected files and verify their integrity, replacing any files with which it finds a problem.