Unless you elevated yourself to full Administrator privileges by disabling Microsoft’s UAC default settings, you are installing/running software with ‘User’ privileges. This is deliberate on Microsoft’s part—security reasons.
I did not know this until recently…I just assumed that since the word ‘Adminstrator’ appeared under my Windows Account Icon and that, like you, I am a sole operator of my personal hardware, that I was doing everything with ‘Administrator’ privileges. That is not the case.
Try this: launch SU two ways: first, just click on any file. Next, right click on SU in the Windows Start menu, right click ‘more’ and Run as Administrator. Go to Task Manager (ctrl alt del) then ‘details’ on the menu bar. Scroll down to Sketchup and you will see one instance of sketchup.exe running elevated, the other is not.
So, I guess we must do our installs with ‘Run as Administrator’ for some reason, but, after that, I do not run SU with elevated privileges. I am not a tech person; I want to operate within Microsoft’s recommended security framework. I wish someone from SketchUp would explain this ‘Run as Administrator’ thing to all of us.