If that's the way you want to install the operating system, then check out our guide on how to download the Windows 11 ISO for more advice. Over the years your PC's hard drive may become filled with unwanted apps and files, so a clean install can get rid of all of that. If you'd like to perform a fresh install of Windows 11, rather than upgrading from Windows 10 (or earlier), then you'll need to download the Windows 11 ISO file.ĭoing a clean install takes a bit more time, and you'll need to reinstall all of your apps and restore your files if you've backed them up (which you should do before you start), but there are many benefits of doing a clean install of Windows 11.įor a start, you'll get a much better performing PC, and if you were encountering any issues with Windows 10, a clean install can help fix some of these. How to download Windows 11 ISO for a clean install This is available in the current Insider builds, but you can only do it within 10 days of upgrading your machine, otherwise a clean install has to be done in order to go to Windows 10. There's also an option to downgrade to Windows 10 if you are experiencing issues with Windows 11.