When you upgrade to the latest version of Windows The prior Windows installation files are saved on your computer. You can set up your computer to delete automatically prior Windows installation files or erase them manually.
Delete previous Windows installation (Windows.old)
If upgrading from the earlier version Windows (7/8) in Windows 10 the computer creates a Windows.old folder. This folder stores the original Windows installation files stored within this directory.
Windows.old folder can also be created when you do an uninitiated install of Windows 10 without formatting the drive that holds the Previous Windows installation.
This security measure is implemented in Windows OS is designed to enable users to go back to the earlier version of Windows in the event that the most recent version isn’t functioning properly.
If, however, the most current Version of Windows is running smoothly it is not necessary to let the previous Windows Installation to occupy too much memory on your system in particular in the event that you are using smaller space on C Drive.
Notice: If you delete the previous Windows installation files then you will not be able to back-upgrade to the earlier versions of Windows (which is likely to not be necessary).
1. Delete the previous Windows Installations by using Storage Sense
If you have the “Storage sense” feature is turned on within your system, the Previous Windows Installations will be immediately removed from your computer within 10 days.
If you don’t like activating Storage Sense, take the following steps to uninstall previous installations that are part of the Windows operating system off your PC.
1. Open Settings > click on the System tab.
2. On System Settings screen, click Storage in the left-hand pane. In the right-hand pane. click the Configure Storage Sense or launch it now.
3. On the next screen you can scroll down the list to select the delete earlier version of Windows option. Click on the Clean Now button.
Then wait until Storage Sense to delete all the files that are associated with prior Windows version from your PC.
2. Delete previous Windows Installations by using Disk Cleanup
1. Click on the Start button, enter Disk Cleanup in the Search bar. Right-click the Disk Cleanup App and click on Run as Administrator.
2. When prompted, enter your Admin Password and then wait for Windows to determine the amount of storage space available on your personal computer.
3. On the next screen, choose Previous Windows Installations, and then select OK.
3. Delete previous Windows Installations using Command Prompt
You can also erase the previous Windows Installation files by using Command Prompt.
1. Right-click on Start and then select the Command Prompt (Admin).
2. On Command Prompt window, type RD /S /Q %SystemDrive%\windows.old and press the Enter key on the Keyboard of your computer.
3. Wait, until the command is complete and you reach another prompt.
NOTE: It usually takes some time to complete this command. Don’t shut down the Command prompt until you are at another prompt.