Microsoft tests feature that lets you reinstall Windows through Windows Update without losing files, applications, etc.

A new Windows Update feature could be a game-changer for those scared of losing files or pictures when attempting to reinstall or recover their Windows 11 installations. The new feature, Fix Problems using Windows Update," lets you reinstall Windows 11 using Windows Update.

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The idea is to repair the existing Windows installation by downloading a fresh copy of the OS from Windows Update. And the best part? It won't remove any files, settings, or apps, according to a support document from July 2023.

Mayank Parmar for Windows Latest

If it works as advertised, it sounds like a useful feature. I wouldn't trust Windows Update with anything more valuable than a used toothpick, but if you're already using Windows, that ship sailed anyway, in which case this is better than nothing.