I hope you're having an amazing day! I am a windows fan and user, just like YOU! I will do my very best to help you solve your issue. I know you have had a bad experience and it must have been very hard for you. But rest assured, i will help you to the BEST of my ability!
And then try DISM.exe /Online /Cleanup-image /Scanhealth and DISM.exe /Online /Cleanup-image /Restorehealth that'll get rid of the 9GB file for sure. If not, reinstall everything again and again and again.
It should fix system files that are not in expected state (I assume corruption, missing, wrong permissions etc.). Maybe it was more useful in the past, but after trying it couple times around 8 years ago and never seeing any benefit, I have never thought of using it since.
My colleague said it fixed some random issue once or twice after he was out of ideas.
If system is truly messed up, it's often faster and more reliable to just reinstall it, especially if you do not have much custom config.
As someone working in the Microsoft ecosystem at an MSP, we seriously wonder what the fuck goes on over there. We’re supposed to defend everything y’all do which is getting really hard to justify without sounding like idiots.