Unity 2019.4.11f1 GUI Bug?

Error : Unloading broken assembly Library/ScriptAssemblies/Assembly-CSharp.dll, this assembly can cause crashes in the runtime
The error pops up after I restart unity every time while trying to work around a different Bug which is any unityengine.GUI related class becomes inaccessible by IDE / Unity.
A quick work around for this is switching .NET version from 2 to 4 in player settings (crashes unity but works after the restart).
Note: this is not limited to my singular project. It happens every time i import a GUI related item onto the project.
Any way to permanently fix this?

  1. Uninstall Unity

  2. Go to %temp% and temp and delete every files there inside ( Skip if pop up )

  3. Download CCleaner and do Analyze Cleaner, Fix Registry

  4. Uninstall Unity hub

  5. Restart PC

  6. Install Fresh Unity hub from unity website

  7. Install unity without visual studio / documentation