100% disk usage on startup (Windows 10)

Hi Joe,

Thank you for posting in Microsoft Community.

We understand that the CPU is showing high usage, it might be due to some internal software conflict. So we would suggest you to perform following methods and check.

Please let us know if the issue is resolved or you need any further assistance.

"We understand that the CPU is showing high usage..."  

No.  The problem is DISK usage.  The generic answers are irrelevant to the problem at hand.

For a much better discussion, see http://answers.microsoft.com/en-us/windows/forum/windows_10-performance/100-disk-usage-on-startup-windows-10/1e73d3db-0faf-410b-bd55-6f1be987c98b

"For a much better discussion, see http://answers.microsoft.com/en-us/windows/forum/windows_10-performance/100-disk-usage-on-startup-windows-10/1e73d3db-0faf-410b-bd55-6f1be987c98b"

Wow!

I am having this issue too. 

I uninstalled my Firewall (COMODO) As it was using 8MB of DISK usage on start up. But that doesn't fix it. System and Compressed memory then uses 20MB of the DISK usage. Rendering my computer useless for at least 5 minutes.

This is a custom built computer I built myself. It only recently started doing this in the past month.  

Once about 5 minutes is up, the DISK usage is brought down to 0% and I am able to do what I need to do.

My start up time used to be 30 seconds. Now it's 1 minute and 45 seconds with NOTHING in start up besides the core windows drivers. I made sure any 3rd party programs like my AV, and Geforce Experience didn't start up with windows, iTunes, Chrome Updater, etc. As it stands the only program that starts up is OneDrive. 

On Startup my CPU and RAM isn't affected by this, just the Disk 0 (C:) I've tried many things, Check disk, and that came up with ZERO errors, defragment, still nothing. I even turned off the Shadow Copy, and the paging file size to 0.

I have 16GB RAM, and 4.1Ghz six core Processor. So, my boot time should be fast, and the Disk shouldn't be used at 100% for 5 minutes at the start of the computer.

I did run a virus scan with Windows Defender, COMODO (Before I uninstalled it) and Malwarebyte's Antimalware (Not all at the same time of course) 

I did what was suggested above, just in case scenario, and absolutely nothing changed.

The link you provided comes right back to this page we are on right now.

This is the link you posted: http://answers.microsoft.com/en-us/windows/forum/windows_10-performance/100-disk-usage-on-startup-windows-10/1e73d3db-0faf-410b-bd55-6f1be987c98b

This is in the URL bar on Chrome: http://answers.microsoft.com/en-us/windows/forum/windows_10-performance/100-disk-usage-on-startup-windows-10/1e73d3db-0faf-410b-bd55-6f1be987c98b

I'm sorry.  The page I meant to link was http://answers.microsoft.com/en-us/windows/forum/windows_10-performance/windows-10-100-disk-usage-on-startup/f7019ace-6eea-4eec-89af-4eefbeccd9a6

The key post is Deepika Gowda who explains how to use Task Manager to see what processes are doing disk I/O.  Here is the key part of what he had to say:

1. Open Task Manager and click on Details tab.
2. Right click the columns headers and click "Select Columns".
3. From the "Select Columns" window, check: I/O Reads, I/O Writes, I/O read bytes, I/O write bytes and then click OK.
4. Now the columns will be added to the view and will display how much each process is utilizing from the hard disk.
5. Sort by I/O read bytes or I/O write bytes by clicking on the column header to see which process is utilizing the Hard Drive most.

Oh it's no problem at all. and sorry for late reply! Was out of town. 

So, I did that, and this seems to be the culprit: msmpeng.exe. Says Antimalware Service Executable, its I/O Reads 991,917, I/O Writes 201,912, Read bytes: 7,743,699,130,  and write byte's of 737,454,363. It's still going. However, even though it says it's Windows Defender said many places online. I have that disabled. What else is alarming, is if it were a virus, you'd think Malwarebyte's Anti Malware, and COMODO Security would have caught it if it were so, i've scanned numerous times before and nothing ever came up. Tried ending the task, and it denies me. 

Now that time has passed, it's gone down to 0% usage. But my uptime has only been 20 some minutes, despite Task manager saying 2 days. (Which is confusing since my entire system was unplugged before I left out of town) 

Hopefully I can figure out how to get this off. It's annoying for the first 5-15 minutes or so. My boot time is now 30 seconds since removing Comodo. 

Next is csrss.exe in line of 42,580 which those numbers move. the msmpeng.exe does not move, has been the same numbers since I've started this. 

" it says it's Windows Defender many places online. I have that disabled. "

Same issue I had. Yes.....HAD. The problem to me does appear to be Defender as you mentioned, and while you think you are disabling it, I believe it continues to run in the background and hog the disk. Read below and give this a try. For me, my computer continues to perform perfectly a week afterwards.

The "Fix" that works (for me).....

Way too many people having this same 100% disk usage problem. Yes, there may be many reasons but it's just as likely it's something simple.

In my case, I came to suspect Defender was at the heart of the problem. Reason: My Task Manager showed "Windows Antimalware Executable" at 100%.

After trying numerous "Fixes," including turning off Defender, (to the extent that it will allow), nothing seemed to work. My fan was running continuously and I was sure my hard drive would self-destruct.

So, suspecting that turning off Defender's "Real-Time Protection" truly didn't shut down completely, I downloaded the free program, "Spybot Search and Destroy." By Microsoft's design, downloading a second anti-virus program will cause Defender to automatically turn off so as to not have the two programs conflicting.

This can be verified by going to Settings / Update & Security / Windows Defender. All selectable items, including "Real-time Protection" will be "greyed out" and no longer switchable (on/off).

So....after dealing with this 100% disk usage problem for over a month, my computer has been running perfectly for the last week. No problems whatsoever. The change was immediate upon downloading SS&D. I have no doubt that you could try other anti-virus programs and get the same result.

This is by far the simplest "Fix" I've tried.....and the only one that actually worked. If it doesn't work for you, simply delete it and go back to Defender. Having said that, I'd prefer to use Defender myself....but I can't tolerate what it's doing to my computer.

Good luck,

Todd

UPDATE: After a week of perfect function and just to verify my suspicions that Defender is the problem, I deleted my Spybot Search & Destroy. This enabled Defender to turn back on.  My Task Managerimmediately showed my hard disk to be running at 100% again. The culprit identified by Task Manager once again as "Windows Antimalware Executable."

So, if anyone can convince me that Defender is NOT the problem here....please chime in. By the way, re-installing SS&D once again "fixed" the problem by automatically shutting down Defender.

If this helps anyone else, leave a reply.....maybe Microsoft will take note.

I also have this problem, with 100% usage of a disk on startup. While it is not my primary disk that is being hogged, I can't access any files until the Windows Antimalware Executable is done doing it's thing.

I found the easy way to negate this issue : Upon startup, go straight to Windows Defender (you can have an icon in the notification tray to get there faster). Switch "Real-time Protection" off and then back on again.

Hey presto!

(although having this problem in the first place is ridiculous - the slow down by this process makes having an SSD a bit of a waste)