The blog of Windows Wally, a Windows Support Technician helping common people solve frustrating computer problems.

Can’t Delete ” Windows.old ” Folder in Windows 10

Reader Question:
“Hi Wally, I have a computer that I upgraded from Windows 7 to Windows 10 using the upgrade option. The upgrade went well. But, I noticed that there was a huge folder in C drive named Windows.old

It is taking a lot of disk space. I tried deleting it once, but it won’t go away Please help me. I need to remove it to free up disk space. Thank You” – Charles A., Australia

Before addressing any computer issue, I always recommend scanning and repairing any underlying problems affecting your PC health and performance:

  • Step 1 : Download PC Repair & Optimizer Tool (WinThruster for Win 10, 8, 7, Vista, XP and 2000 – Microsoft Gold Certified).
  • Step 2 : Click “Start Scan” to find Windows registry issues that could be causing PC problems.
  • Step 3 : Click “Repair All” to fix all issues.

Setting up weekly (or daily) automatic scans will help prevent system problems and keep your PC running fast and trouble-free.

Wally’s Answer: Many Windows users have gone through the process of upgrading from Windows 7 to Windows 10. However, many of them complain about the big Windows.old folder on their hard drive.

Here, we will tell you what that folder is; if you should remove it; and how you would remove it from your computer.


The user is not able to delete the Windows.old folder from the system partition. The folder is found in C:\Windows.old unless the user installed Windows on some other partition. The following error may appear when trying to do so:

“You need permission from SYSTEM to make changes to this folder”

Windows.old -- You need permission to perform this action - Cover - Windows Wally

And, sometimes, the following message:

“You require permission from TrustedInstaller to make changes to this file”


Here is how to remove the Windows.old folder from the hard drive in Windows 10.

What Is The Windows.old Folder?

The Windows.old folder is created when you upgrade from one version of Windows to another. It contains files from each user’s profile and settings from the previous version of windows. This folder is very important if you want to downgrade Windows back to the previous version.

Remove The Windows.old Folder Using Disk Cleanup

The easiest way to remove the Windows.old folder from the computer is by using the Disk Cleanup utility built-into Windows.

  1. Press the Windows Key and type Disk Cleanup to search for it. Click the Disk Cleanup utility icon to launch it
  2. Select the System Partition. It is usually C:
    If you’re not sure, then click the one with the blue flag icon. Then, click OK.
    Speed Up Your Windows - Disk Cleanup - Launch -- SolvuSoft
  3. Wait while Disk Cleanup launches.
    Low Disk Space - Disk Cleanup - Calculating - SolvuSoft
  4. Select the files that you want to remove from your computer. You can select all of these files if you want. The Windows.old folder should also be listed as Previous Windows installation(s).
    Low Disk Space - Disk Cleanup - OK -- SolvuSoft
  5. When you’re all set, click OK to continue.

Disk Cleanup Error: Some Files Are Still In Use 

If Disk Cleanup refuses to delete some files saying that they are “still in use” then you can try to delete them by starting Windows in Clean Boot mode. There is a chance that some program is using these files, and starting in Clean Boot can unlock these files.

Click here to learn how to start Windows in Clean Boot mode.

I Hope You Liked This Blog Article! If You Need Additional Support on This Issue Then Please Don’t Hesitate To Contact Me On Facebook.

Is Your PC Healthy?

I always recommend to my readers to regularly use a trusted registry cleaner and optimizer such as WinThruster or CCleaner. Many problems that you encounter can be attributed to a corrupt and bloated registry.

Happy Computing! :)

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About the Author

Windows Wally is a helpful guy. It’s just in his nature. It’s why he started a blog in the first place. He heard over and over how hard it was to find simple, plain-English solutions to Windows troubleshooting problems on the Internet. Enter: Windows Wally. Ask away, and he will answer.