Windows 10 Bug Could Strain Hard Drives

John Lister's picture

Microsoft is testing a fix for a bug that could theoretically shorten the lifespan of some hard drives. The bug means Windows 10 was mistakenly running the defrag tool more frequently than designed.

Defragging has long been available as a way to make hard drives run more efficiently. It deals with the problem that when a computer deletes a file, it leaves empty physical space behind on the drive. The next time it writes a new file it will look for the first available suitable sized space.

Over time this can lead to wasted gaps on the physical drive. In turn, this means traditional hard drives have to move the head (which reads the data) further back and forth to reach files. This only takes fractions of a second longer, but can add up quickly and severely impacts overall performance on the system.

In simple terms, defragging rearranges the files to remove the gaps, reducing the distance the head has to move to reach any particular file.

Defragging SSDs Not Worthwhile

While defragging was recommended back in the day, modern computers with solid state disks (SSDs and NVMes) are much more efficient in handling files, so it's not usually necessary. The reason for this is because the newer style hard drives don't have read/write heads or spinning platters and therefore there is no latency when attempting to access files.

Many tech experts believe the wear and tear of effectively rewriting most files on such drives outweighs the limited benefits of defragging. Even those who believe it is worthwhile suggest only doing it occasionally.

Optimize Drives Not Working Optimally

Windows 10 does have a built-in defragging tool named Optimize Drives, but it's set to only run on a limited schedule, such as every two weeks or once a month. However, a bug in a recent update means the tool isn't correctly identifying when it last ran, and in some cases, is running every time a computer restarts. For some users that could mean it runs 30 times more often than it should. (Source:

With traditional hard drives, this shouldn't be a major problem, though it could cause some delays. With SSDs, Optimize Drives will normally not attempt defragging, but instead use a harmless alternative technique called TRIM.

However, Windows may attempt to defrag on an SSD if users have particular settings in the System Restore tool switched on. That could mean an increase in physical strain on the drive. (Source:

Microsoft has acknowledged the problem and is testing a fix through the Windows Insider program. It will then roll it out to the general public if all goes well with the test.

What's Your Opinion?

Do you intentionally defrag hard drives, either manually or automatically? Do you know off-hand whether your computer users traditional or solid-state hard drives? If you made a deliberate choice between the two, what influenced your decision?

Rate this article: 
Average: 4.7 (9 votes)


anniew's picture

Could this be related to having a huge cache removed by CCleaner a couple of times? I run it each evening and where there are usually 400,000 kb in one area, there were 900,000 one time and over a million the next. Very unusual. I'm wondering why this happened. I didn't think a defrag would remove items from the hard drive.

Dennis Faas's picture

A disk defrag doesn't delete items from the hard drive. It removes random gaps between files that are scattered all over the media and replaces them into contiguous space. This means the hard drive doesn't have to move back and forth all over the media to access a file, which translates to faster access to said files.

ronangel1's picture

This is not good and could shorten life of ssd hard drives. do you have a fix?

Tex Dad's picture

"...particular settings in the System Restore tool switched on."

OK, so changing these settings would be a temporary fix/workaround.
What are the settings?

rohnski's picture

I'm with Tex, while the article is 'nice', why are you teasing us with a workaround that you keep secret.
I NEED to know the secret voodoo incantation to save my SSD from the evil MS bug monster.
Please share ...

beach.boui's picture

In the time you took to complain about not having the secret voodoo incantation, you could have executed a search on the Google or Bing search engine that would produce plenty of leads on the subject.

SaiMorphX's picture

Open File Explorer -> This PC -> Right click any drive -> Properties -> Tools -> Under Optimize and defragment drive -> Click Optimize -> Under Scheduled optimization -> if it says On, Click Change settings -> The first Checkbox, Run on a scheduled (Recommended), unchecked it, and click Ok!

You're done! Check or analyze your drives yourself once a week until they fix this.

bhoughtaling's picture

I want to try this, but I can only get as far as the "Optimize" button. I click on it and it brightens for a little as if something will happen, but that's it. Nothing noticeable happens. Suggestions?

SaiMorphX's picture

Not really sure, are you in Administrator mode, I'm not sure? are the drives mounted right? is there another program that has taken over drive optimization?

Draq's picture

So far, I haven't had a computer with an SSD in it. It would be weird not hearing the drive when it's working.