Windows 7 Forums
Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.

Windows 7: explorer.exe runs at 100%

01 Jul 2011   #1

All of them
explorer.exe runs at 100%

Ok, it actually runs at 50%, but I have a dual core, so it is 100% of one core. I have used Process Explorer from SysInternals to find out which thread (and it's call stack) is eating up all the CPU. What I have found is the ntdll.dll is using all the CPU and here is the call stack:


I have wiped my machine 100% clean and reinstalled fresh, slowly over about a two week period, the problem is back. I don't have a clue why. Any thoughts on how to track this down?

My System SpecsSystem Spec
01 Jul 2011   #2

Microsoft Community Contributor Award Recipient

Windows 10, Home Clean Install

What I would do for a starter is to make a clean boot, with luck you will be able to see what software is using the dll
My System SpecsSystem Spec
02 Jul 2011   #3

All of them

What do you mean by "make a clean boot"? Do you mean reinstall the whole machine AGAIN? This is not my personal computer, it is my work computer. The IT department does the initial install because they HAVE to put this HD encryption software on the machine. It turns out that this last install was the first time I got this encryption software on my laptop. Mind you, this 100% CPU issue happened on the old install, too, so the encryption software is NOT the cause of the problem.

But what this HD encryption does mean is that I cannot do some things others can do, like boot off a CD and read my hard drive. I have to boot the OS as is, no if's and's or but's!
My System SpecsSystem Spec

02 Jul 2011   #4

Microsoft Community Contributor Award Recipient

Windows 10, Home Clean Install

No, a clean boot is not a new install.
It is a simple procedure, by ticke marks, that do not allow certain software to load up during boot. It is meant to see if one of these programs is the cause of your problems.
My System SpecsSystem Spec
03 Jul 2011   #5

Windows 7 64b Ultimate

Have you checked with collegues if their LT show the same CPU usage?
I've seen this multiple times in situations where, on new installs, on the company network, it takes ages for the system to stabilize, run all kinds of stuff the IT boys thought was good to run, even up to licence scanners etc...
Iow, are you the only one?
My System SpecsSystem Spec

 explorer.exe runs at 100%

Thread Tools

Similar help and support threads
Thread Forum
WDC Green: 750 GB runs Hot, 4 TB runs Cool ???
I have two external hard drives, both in Vantec NexStar3 USB enclosures. The older 750 GB WDC Green drive runs HOT to the touch, the 4 TB, and the 2 TB before that, run pretty warm but never hot. Why might this be, and would that much heat cause earlier than necessary drive failure?
Performance & Maintenance
Validation runs over and over and over and over
Win 7 Pro 64bit SP1. When I was running 32-bit I used the VM and XP. Now upgraded MB and OS to 64-bit. Trying to download the files but the validation process repeats over and over. Windows is legal. Firefox 19.0 Cookies on. Tried with firewall off. Microsoft have never ever answered this...
Computer runs really slow in normal mode, but runs fine in safe mode
I recently re-formatted my Sony VAIO since it was starting to run super slow. Now that I re-installed Windows 7 on it through recovery disks, it worked fined for about a day but then the problem came back. The computer is slow at bootup and runs super slow while freezing so many times. I am running...
BSOD Help and Support
hp dv with win 7 still runs
just replaced the motherboard on my dv9205 with a later model dv9913 motherboard works ok everything on the screen is a little wide the graphics card rating in windows 7 system properties is 1.0 should be a 4.1 and it runs superpi slow 45 sec but downloads transfers files ok could this be i need...
General Discussion
Explorer never runs
Basically, whenever I boot up W7, explorer says it must be closed down. So when I rerun it through Task Manager, it gives me the same crappy error + it want's the software that opened it to close. I thought it was the data execution thing that was causing this, so i managed to reach that and added...
General Discussion

Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd

All times are GMT -5. The time now is 01:44.
Twitter Facebook Google+ Seven Forums iOS App Seven Forums Android App