Thank you for reaching out through the Microsoft Q&A forum.
The difference between the total used space (64 GB) and the sum of app sizes (40 GB) is quite common and can be attributed to several factors:
- System and hidden files: Windows reserves space for updates, recovery, and system operations.
- App data and caches: Many apps store extra data in hidden folders like AppData, which isn’t shown in app size.
- User files: Documents, downloads, and media files also take up space.
To better understand what’s consuming space, I recommend using Storage Sense in Windows settings, it provides a helpful breakdown and cleanup options.
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