Software & Apps Windows How to Delete the Windows.old Folder in Window 10, 8, and 7 Remove previous Windows installation files to free up hard drive space By Scott Orgera Writer Scott Orgera is a former writer who covering tech since 2007. He has 25+ years experience as a programmer and QA leader, and holds several Microsoft certifications. our editorial process Facebook Twitter Scott Orgera Updated March 21, 2019 Daniel Sambraus / Photodisc / Getty Images Windows The Ultimate Laptop Buying Guide Tweet Share Email If you've upgraded to a new version of Windows at some point, then a significant portion of your previous operating system's files are likely still sitting on your hard drive in a folder named Windows.old. Deleting these files can free up precious space on your PC. Instructions in this article apply to Windows 10, 8, and 7. How to Delete the Windows.old Folder To delete the Windows.old folder: Do not delete the Windows.old folder if there's a chance that you may want to revert back to the previous operating system in the future. Type disk cleanup in the Windows search box and select the Disk Cleanup app from the list that appears. Select the Start Menu to access the search box in older versions of Windows. Select Clean up system files. Disk Cleanup will analyze your hard drive and calculate how much space it can clear up. Once scanning and analysis are complete, the Disk Cleanup window will re-appear with new options listed under Files to delete. Check the box beside Previous Windows installations (or Older versions of Windows), then remove the checkmarks next to other items in the list (unless you want to delete them from your hard drive as well) and select OK. If you do not see these options available, then Disk Cleanup didn't find any old Windows files on your PC.