I just updated my HP Victus 16 laptop from Windows 11 version 23H2 to 25H2 using an ISO file because my system had issues with the updater. I previously held off on upgrading due to the need for stability while I was in school. Now that I'm graduated, I decided to go for it. After the update, the space used on my C: Drive went from 170GB to 210GB. Initially, I suspected temp files were taking up a lot of space, but a detailed check showed only about 422MB. I'd like to understand why this increase occurred and if there's a way to recover some of my storage.
5 Answers
Not exactly a fix for your current situation, but if you really want to reclaim space without figuring out what's taking it, consider doing a clean install from a USB drive. It’ll give you a fresh start without the old clutter.
Honestly, Windows storage can be misleading at times. I recommend trying a tool like WizTree for a more accurate analysis of what's hogging your space. Also, after an upgrade, check if you have a 'Windows.old' folder on your C drive. It stores the previous OS version in case you want to go back, but it can also be removed with Disk Cleanup—make sure to use the option for deleting system files.
TreeSize is another handy tool you can use to visualize where your disk space is being taken up. Often, there are hidden temp files that Windows doesn't account for, and this can help discover them.
When Windows upgrades, it typically keeps the previous version for about 30 days for easier recovery. You can delete the old version using Disk Cleanup if you’re confident you want to stay on the new version. That should clear up some space.
Make sure you run Disk Cleanup and check the option for system files to clear out Windows update files. You might also consider using WizTree to pinpoint larger files. Just be cautious about deleting stuff—you want to know what you're removing, especially within the Windows folder.

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