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Disk at 99% in Windows 10? You Can Fix It in 8 Steps

Check expert ways to reduce disk usage and improve performance

7 min. read

Updated onOctober 4, 2023

updated onOctober 4, 2023

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Key notes

The disk is an integral part of the computer and is used to store files.High disk usagetypically refers to a situation where a large part of the disk is being actively used by the PC to run programs and tasks. And problems appear when disk usage hits 99% in Windows 10.

Anything above 90% can affect the PC’s performance and significantly slow it down. Some even reported Windows 10 high disk usage on startup. No matter the case or when you face the problem, there are a few solutions that might help. Keep reading to find out!

Why is my disk running at 99 in Windows 10?

Here are a few reasons you are witnessing 99% disk usage in Windows:

How do I fix 99% disk usage in Windows 10?

Before we head to the slightly complex solutions, here are a few quick ones to try:

If none work, move to the fixes listed next.

1. Manually terminate programs

When terminating programs and processes, make sure not to kill a critical one, as it might affect the device’s functionality. For instance, if you terminate the process pertaining to audio, there will beno sound on the PC.

2. Disable non-critical services

Once done, restart the computer and verify whether the 99% disk usage in Windows 10 reduces to normal levels. And don’t look at the immediate effect. Rather, monitor it over an extended period for accurate results.

3. Turn off notifications and tips

The notifications and Windows tips and tricks often result in increased CPU usage, sometimes as high as 99% in Windows 10. Disabling it did the trick for most users!

4. Run the CheckDisk utility

Check Disk is a built-in utility in Windows that helps fix errors that appear while scanning the disk and repairs corrupt sectors. Both may result in 100% disk usage even when nothing is running. So, it’s imperative that you run the Check Disk utility tofix disk issues.

5. Repair the corrupt system files

Corrupt system files, too, may affect the functioning of the device and lead to 99% disk usage in Windows 10. In this case, theDISM commandsand SFC scan should do the trick.

6. Perform a clean boot

Once the PC restarts, check whether 99% disk usage in Windows 10 subsides. If it does, one of thedisabled startup appsor services is the underlying cause.

Again, openSystem Configuration, enable them one at a time, restart the computer after each, and verify whether there’s an increase in disk usage.

As soon as you notice a change, the service/program enabled last is the culprit. So, have it disabled, at least for the time being, until an update is released.

7. Reset the virtual memory

While many recommendincreasing the Virtual Memory, it’s often best to let Windows set the right size. Change it only when you are facing issues pertaining to performance or theRAM usage is high.

8. Perform an in-place upgrade

Arepair upgradeis often used as a last resort but helps fix various issues with Windows. It replaces the current OS installation with a new one without affecting the stored data, installed apps, or configured settings.

Now that you have fixed 99% or higher disk usage in Windows 10, check some quick tips toincrease the data transfer speed on the PC.

For any queries or to share which solution worked for you, drop a comment below.

Disk at 99% in Windows 10? You Can Fix It in 8 Steps#

Why is my disk running at 99 in Windows 10?#

How do I fix 99% disk usage in Windows 10?#

1. Manually terminate programs#

2. Disable non-critical services#

3. Turn off notifications and tips#

4. Run the CheckDisk utility#

5. Repair the corrupt system files#

6. Perform a clean boot#

7. Reset the virtual memory#

8. Perform an in-place upgrade#