Usually Windows.old folder consists of all of your system files your previous OS used. You can use this folder if you want to access any file saved in your older Windows. Sometimes you do not need your old Windows as you have copied all of the important files to your current Windows and you intend to remove the folder Windows.old from Windows 8.1.
The majority of the users does not know how to remove this folder from Windows 8.1. I have put here a very useful tutorial for all of you on how you can remove Windows.old from Windows 8.1 in a few steps.
Steps to Remove Windows.old from Windows 8.1
Step 2: A new Window will open before you that contains the Hard Disk Drives. Here, you need to right click on C: Drive and select the option “Properties” from the menu appears.
Step 3: Now you will see the Properties menu of Windows 8.1. Click on the “Disk Cleanup” button.
Step 4: It will take you to another window where you need to select the option “Clean up System Files” at the bottom of the screen.
Step 5: As you select the above mentioned option in the previous step, the system will start checking for the System Files you want to clean up as it has been shown in the image below.
Step 6: Now a window appears before you where you need to check the option “Previous Windows Installed” and click on the “OK” button. It will remove the Windows.old folder from the Windows 8.1 within a few seconds.