How to Delete Previous Windows Installation Files in Windows 11 & 10

Old Windows installation files occupy a lot of storage space. Here is how to delete previous Windows installation files in Windows 11 & 10.

When you upgrade to a new Windows version, it keeps the previous installation files intact. Consider it a backup of your previous Windows installation. If you don’t like the new version or are having problems with the new update, the old Windows installation files can help you downgrade to the previous version.

Typically, these old Windows installation files will be anywhere from 10GB to 30GB. The size of them is determined by a variety of factors such as installed updates, apps, settings, and so on. As you might expect, that’s a lot of free hard disk space. If you are certain you will not downgrade, deleting these previous Windows installation files will help you free up disk space.

There are two methods for removing old Windows installation files. Using the Storage Sense and Disk Cleanup programs, for example. The simplest and quickest approach to removing old Windows installation files is to use Storage Sense. Both ways accomplish the same thing.

Without further ado, let me walk you through the methods to erase previous Windows Installation files in Windows 11 and 10.

Warning: Once you’ve deleted the old Windows installation files, you won’t be able to revert to an earlier version of Windows.

Table of contents:

• Delete previous Windows installation files in Windows 11
• Remove previous Windows installation files in Windows 10
• Use Disk Cleanup to delete old installation files

Delete previous Windows installation files in Windows 11

In Windows 11, the previous installation files are considered Temporary Files. That means you can delete the old installation files using the Settings app. Here’s how.

1. Open the Settings app.
2. Click “System” on the sidebar.
3. Go to the “Storage” page.
4. Click on the “Temporary files” option.
5. Select the “Previous Windows installation(s)” checkbox.
6. Clear all other checkboxes.
7. Press the “Remove files” button.
8. Close the Settings app.
9. With that, the previous Windows installation files are deleted.

Remove Old Windows Installation Files in Windows 10

In Windows 10, there is a new feature called Storage Sense. This feature allows you to delete the previous Windows installation as well as any other temporary files. Storage Sense is considerably easier to use than old programs, and you can even schedule it to automatically delete temporary files.

1. Open the Settings app.
2. Click “System” on the main screen.
3. Go to the “Storage” page.
4. Click on the “Configure Storage Sense or Run it Now” option.
5. Select the “Delete previous version of Windows” checkbox.
6. Clear all other checkboxes.
7. Press the “Clean now” button.
8. Close the Settings app.
9. With that, the previous Windows installation files are deleted.

Steps with more details:

As with most features, the new Storage Sense feature is in the Settings app. So, press the “Win + I” keyboard shortcut to “open the PC Settings app.”

Go to the “System -> Storage” page on the Settings app. Click the “Configure Storage Sense or Run it Now” link appearing right under the “Storage” section on the right panel.

Here, under the “Free up space now” section, select the “Delete the previous version of Windows” checkbox and click on the “Clean now” button.

As soon as you click on the button, Storage Sense will delete previous Windows installations.

Use Disk Cleanup to delete old installation files

If you want, you can also use the Disk Cleanup Tool to remove old Windows installation files. The good thing about Disk Cleanup Tool is that it works in Windows 10 and 11.

1. Open the Start menu.
2. Search and open “Disk Cleanup.”
3. Select “(C:)” from the dropdown menu.
4. Press the “Ok” button.
5. Press the “Clean up system files” button.
6. Select “(C:).”
7. Select the “Previous Windows Installation(s)” checkbox.
8. Press “Ok.”
9. Click “Yes” when prompted.
10. Previous Windows installation files are deleted.
11. Close the Disk Cleanup tool.
12. Reboot Windows.

Steps with more details:

Open the start menu, search for “Disk Cleanup” and open it. Alternatively, type “cleanmgr” in the Run dialog box and hit “Enter.”

Select “(C:)” from the drop-down menu in the Drive Selection box and click the “Ok” button.

Since the old Windows installations are considered system files, click on the “Clean up system files” button appearing at the bottom.

The above action will restart the Disk Cleanup tool. So, select (C:) from the drop-down menu.

Now, find the “Previous Windows Installation(s)” option, select the checkbox and click on the Ok button.

If a confirmation window appears, click the Yes button to proceed.

As soon as you click the Yes button, Windows will delete the previous installations.

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That is all. It is that simple to delete old Windows installation files. Sometimes, you might also see Windows WS and Windows BT folders. These are also old installation and update files. You can delete them to free some more space.

I hope this simple and easy Windows how-to guide helped you.

If you are stuck or need some help, send an email, and I will try to help as much as possible.

Image credit: Matti Mattila