[Resolved] Cannot Delete the Windows .old Folder as Access Is Denied

Why can’t I delete the Windows .old folder access denied?

"I just upgraded my PC from Windows 10 to Windows 11 today. After the upgrade, I found there was little free space left on the C drive. After having a thorough examination, I found a folder with the suffix of ‘'old' occupied much space. I tried deleting it. However, I was prompted that the folder access was denied. What’s this Windows .old folder and how to delete it once for all? Can anyone give a solution?"

What’s the Windows.old folder?

Sometimes, you may notice a folder suffixed with "old" placed under the folder of Windows in the C drive which could take up large storage space. Then, what's the Windows .old folder?

An OLD file is a backup copy that's generated by the Windows OS when you upgrade from one Windows version to another. This sort of folder isn't something new as it started from Windows Vista.

The Windows .old folder has all files and data from your previous OS installation, including system files, user account settings, user profiles, user folder files, etc.

The Windows upgrade may go wrong sometimes and thus, a Windows .old folder works. It helps restore the OS to the previous state as it holds a collection of critical OS files.

Is it okay to delete the Windows .old folder?

The Windows .old folder can take up very large space sometimes up to 20GB. So, many people hope to permanently remove it from their PCs. However, will deleting the Windows .old folder cause any system errors? The answer is negative as the folder doesn’t contain any critical system files but only some backups.

How to delete the Windows .old folder?

When people try deleting the Windows .old folder from the C drive, many of them report that they’re prompted with a "Folder Access Denied" warning that stops them from proceeding. So, how to delete the Windows .old folder under such a circumstance? In the following paragraphs, you can learn to use several Windows built-in programs to make it.

Preparations before the folder deletion

There’re preparations that should be done before .old folder deletion.

Make a backup of the .old folder

As mentioned above, the Windows .old folder contains some important files for system restoration. So, in case of any system failure in the future, you're suggested to make a backup of the .old folder before deleting it.

Acquire administrator permission from the system

You could fail in deleting the Windows .old folder without administrator permission. If you have several user accounts on the PC, switch to the administrator account as follows:

1. Open the Windows start menu from the bottom left and select your username

2. Hit "Administrator" on the list.

3. Sign in with the PS of your administrator account.

Method 1. Use Windows Disk Cleanup

Although the Windows built-in program Disk Cleanup is usually used to clean junk files like cache and cookies from your hard drive, it's capable of deleting the Windows .old folder once for all. Here, we take Windows 10 Disk Cleanup for example.

1. In the "Type here to search" box at the bottom left of the desktop, type "disk cleanup".

2. Select "Disk Cleanup" under "Best match".

3. Select the C drive and hit the "OK" button.

4. Click on "Clean up system files".

5. Then, you may need to choose the C drive again and hit "OK".  Wait until the scan completes.

6. Tick the option "Previous Windows installations" and click on "OK" to delete the Windows .old folder.

Method 2. Try Windows settings

Another way to effectively delete Windows .old folder is to open up Windows settings and remove temporary files.

1. Open the start menu and click on the gear icon to launch the settings app.

2. Go to "System > Storage > This PC (C:) > Temporary files". Click on "Temporary files" and after the scan, tick the option "Previous Windows installation".

3. Click on "Remove files" to delete the Windows .old folder for good.

Method 3. Turn to Storage Sense

Storage Sense is a Windows 10 built-in program that automatically frees up disk space for you by removing items that you don’t need, including TMP files and contents in your recycle bin. Here, you’ll learn how to delete the Windows old folder with it.

1. Open the start menu and got to "Settings > Storage > Change how we free up space automatically".

2. Tick the option "Delete previous versions of Windows" and hit "Clean now".

Once done, the Windows .old folder will be removed from your computer.

Method 4. Apply Command Prompt

The last tool you can try is Command Prompt – a command line based program that helps manage your hard drives and partitions efficiently.

1. In the “Type here to search” box at the lower left of the desktop, type “cmd”.

2. Select "Run as administrator".

3. In the popup window, type the following 3 lines and hit "ENTER" after each of them:

takeown /F c:\Windows.old\* /R /A /D Y
cacls c:\Windows.old\*.* /T /grant administrators:F
rmdir /S /Q c:\Windows.old

How to fix insufficient C drive storage space?

The reason why you want to delete the Windows .old fold is most likely that you find the C drive is running out of space. However, as mentioned before, the .old folder can be important if you want to restore the operating system. So, are there any ways to resolve the issue of insufficient storage on the C drive without deleting the .old folder?

Luckily, the most powerful third-party disk manager – AOMEI Partition Assistant Professional – is able to perfectly enlarge the C drive space with free space allocation and free up the disk space by moving large apps to another drive.

Way 1. Allocate free space

In this way, you can transfer free space to the C drive from another drive like D, E, and F once they have extra space.

Step 1. Install and launch AOMEI Partition Assistant Professional, right–click on the drive that has extra free space, and select "Allocate Free Space".

Step 2. Customize the amount of space you want to allocate and then, select the destination drive.

Step 3. Hit "Apply" where the screenshot shows to commit the operation.

Way 2. Move apps to another drive

To free up the C drive space, you can try moving its apps, especially those large ones, to another drive.

Step 1. Run the AOMEI product. Click “Free up” on in the top toolbar, and choose “App Mover”.

Step 2. Select the C drive and click on "Next".

Step 3. Tick the apps you want to move, select the destination drive, and click on "Move".

Step 4. Hit "OK" to confirm the prompt and then, the app transferring process will start.

Step 5. After it’s done, click on the "Finish" button. Now, check whether the transferred apps run normally. If not, you can restore them to the previous location.

Conclusion

How to fix it if you cannot delete the Windows .old folder as access is denied? In the paragraphs above, you’ve become familiar with the top 4 Windows built-in methods to permanently delete the Windows .old folder. Meanwhile, to resolve the issue of insufficient C drive storage space, AOMEI Partition Assistant Professional should be our first choice as it’s able to enlarge the C drive space by allocating free space and free up the C drive space by moving its apps to another drive. Of course, what AOMEI Partition Assistant can do is far beyond them, if you go further, you’ll discover more powerful features like partition merging, OS to SSD migration, and schedule defrag. To use this software on Servers, you can try the Server edition.