You can delete the
.vs folder without problem because it contains temporary files, user cache data and some others things like with a net browser. It is the same with .suo and .user files.
You can try to uninstall and reinstall Visual Studio as well as use the Cleanup Tool :
You also should delete all registry keys like :
And drive folders like :
c:\Program Files [& x86]\Microsoft Visual Studio [...]
c:\ProgramData\Microsoft Visual Studio\
After that, you may want to run a registry cleaner like CCleaner or Yamicsoft Windows Manager.
If it does not work… the last action is to reinstall Windos itself if you don’t find anything to solve that. Before doing that you can try Visual Studio 2017.