C Drive 100% Usage Hang

I posted this issue in a couple of other threads and thought it was fixed. I'll start a new one to focus in on the issue. At various times the C drive (HDD SATA) usage will go to 100% and stay there for many minutes. Eventually it will come back down to normal, but if you had tried any mouse clicks while it was pegged, it can take up to 15 min. to settle and execute things. I ran CCleaner to clear out any left over files from browsers, the system, and Windows apps. I then set up CHKDSK to run on restart. CHKDSK found no issues. Then I ran SFC /SCANNOW which came back with no integrity violations. DISM SCANHEALTH showed no store corruptions and DISM RESTOREHEALTH competed successfully. CHRYSTALDISKINFO showed only the one reallocated sector for the drive. The driver for this HDD is shown to be current and Windows troubleshooting shows the drive is operating properly. Looking at Task Manager, it appears there are three things that will make the drive show 100%.
1. FireFox v. 110.0.1 and its 13 processes can send the drive to 100%, but sometimes releases it.
2. Norton360 can also send the drive to 100%, but drops off quickly if a process accesses the drive.
3.NTOSKML.EXE will send the drive to 100% every time and once there, the usage stays at 100% even if the process isn't using any resources.
The only other issue I see with this drive is boot up will state the drive may not be available, to press the space bar to continue with the boot up, which completes normally. It also states to check with the drive maker, who has nothing posted about this particular drive model. The system runs just fine when the drive isn't consumed, but hangs when it is. I'm at a loss as to a fix, but if this continues, I'll likely replace the system, since it's 14 years old. Just not in the mood for migration to a new one. Thanks is advance for listening. I wonder what other diagnostic tools I could use to identify the culprit.

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After four hours:
I restarted the system and launched Chrome along with Task Manager to watch the system. NTOSKML.EXE will send the drive to 100% and the disk response times will go over 100,000 ms. If Chrome was accessed during this time, it would rise to the top of the process list, but the disk stayed at 100% and Chrome and TM both went to "not responding" for many minutes. Eventually, Chrome responded and things settled down to normal. I didn't launch FireFox during this period. Lacking any other guidance, I will restore a MR system image from before the last CUM update and see what happens.

Yeah, Norton360 is running all the time and runs a full system scan every Friday night. At one point, I thought it was a hang culprit, but even if it is using 100% of the drive, it will release to another process that accesses the drive. I just saw NTOSKML.EXE lock up the drive and when I selected a new web site on Chrome, the response time went through the roof (over 10,000 ms) and Chrome just stalled for about five minutes until NTOSKML.EXE finally let go of the drive after a bunch of other system processes finished. I will restore the system image tomorrow when I have time.

Update: Just repeated this scenario with the same results except that the disk response times were over 40,000 ms. I don't know what the kernel is doing, but the impact is the system is behaving much differently than before the Feb. B cycle updates.

Update: Another instance and I noticed something I hadn't before. This time the avg. response time was over 100,000 ms. and I saw NTOSKML.EXE was almost doing just reads and no writes. Long response times and just disk reads. Corrupt program or files?

winkey + R perfmon.exe

Create a new User Defined, Data collector set and put it on diagnostics setting. Call it what you want and then save it to the desktop make sure it saves into an actual directory on the desktop as it will create lots of files.

Once you have created the Data Collector then right click on it and start it. Let it run for a few minutes like across the disk spiking to 100% and then stop it and then go to the directory on your desktop that you create and read report.html.

There will be lots of stuff about what the PC is doing and also about the Disks the MFT and FS etc. Try to narrow down the culprit/s and try to see what is happening with those process that are hogging the disk.

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Come to think of it i don't think ntoskrnl.exe would show in task manager as running a process to the user as the task manager is about user space applications and ntoskrnl.exe is kernel space which is all hidden.

Also the capitalization you wrote NTOSKML.EXE is off it should be lower case and its spelt wrong. Unless this is a typo by you then this is a bad sign too.

i would be honing in on this process and you need to verify it. I would start by finding where it is running from use task manager and open its file location it should be located in C:\Windows\System32 it also should be around 10mb in size and it should also be digitally signed by Microsoft and you should also want to hash check the file to see that it checks out.

Apologies. The offending process is listed by Task Manager as System. Properties shows it as ntoskrnl.exe. That's what I get for not using my glasses. I capitalized it to highlight it in the posts. ntoskrnl.exe is 10.3 mb and is signed by MS.

Did a. full system image restore from mid-December and the issue with ntoskrnl.exe went away. However , the drive still goes to 100% and stays there. It doesn't lock things up, but some tasks can get really slow. Even though all tests don't show anything amiss, I suspect the drive is going south. I've spent enough time flogging this problem. We got 14 years out of a $450 computer. Time for a new one. Thanks for the help.