Hi Tristan,
If you are looking for an official and clean way to do this, there is not. There is people who modifies Windows to distribute a lightweight ISO, but it's not official at all. A 35 to 45 GB Windows folder on a fully patched Windows 11 system is actually normal and expected.
These are the methods I use to remove everything when I format.
First, uninstall the obvious stuff. Open Settings > Go to Apps > Installed apps. In the search box at the top, type names like Clipchamp Solitaire, Xbox, News, Weather, and uninstall.
For Copilot: On current builds Copilot is an app that can also be removed through Settings > Apps > Installed apps > Copilot > Uninstall, or via the Start menu All apps list where you can right click Copilot and choose Uninstall.
Next, some things that feel like bloat are the optional features. For example legacy media components, language packs, or tools like Steps Recorder. Open Settings > Apps > Optional features. Scroll the list and remove anything you are 100 percent sure you never use, for example legacy Windows Media Player, Steps Recorder, XPS Viewer, etc.
Also, Windows keeps old versions of components under WinSxS so you can uninstall updates. That is a big part of why the Windows folder looks so large. You can ask Windows to do a safe cleanup of superseded components. Open an elevated Command Prompt (right click Start > Terminal (Admin)) and run:
dism /online /cleanup-image /startcomponentcleanup
For businesses only. Mentioning this just so you know what Microsoft is doing on the Enterprise side.
On Windows 11 Enterprise and Education 25H2 and later, there is now a built in policy called "Remove default Microsoft Store packages from the system" that lets admins centrally remove default apps like Copilot, Clipchamp, Solitaire, Xbox, etc. using Group Policy or Intune, and have them stay gone for all users and after upgrades.
Now, about your 40 GB Windows folder and slow boot. A few realities here:
- Size: A fully patched Windows 11 23H2 or 24H2 with .NET, drivers, language packs, and the component store easily lands in the 35 to 45 GB range. That by itself does not usually cause slow boots as long as you have enough free space (at least 20 to 25 percent of the SSD free) and the drive is SSD, not old HDD.
- Why it feels fast at first and slower after a few days: After a clean install Windows spends several days doing indexing, Store updates, Defender scans, driver updates, and servicing tasks in the background. After big updates it repeats some of that. If the hardware is on the lower end (4 GB or 8 GB RAM, slower SSD or eMMC), this can make the system feel like it has aged very quickly.
- What actually helps performance: Boot and general responsiveness are driven much more by RAM, disk speed, background processes, and drivers than by shaving a few more apps from the image. You already trimmed startup apps, so the next level if you want to go there would be a proper boot trace using Windows Performance Recorder to see what exactly slows down boot.
If you tell me roughly how much RAM and what kind of drive your slowest Windows 11 machine has, I can tailor the next step.