For me this solved the problem:
"First, make sure all instances of Sketchup and LayOut are closed.
Go to C:\Users\username\AppData\Local\SketchUp\SketchUp year\SketchUp and delete the PrivatePreferences.json file."
For me this solved the problem:
"First, make sure all instances of Sketchup and LayOut are closed.
Go to C:\Users\username\AppData\Local\SketchUp\SketchUp year\SketchUp and delete the PrivatePreferences.json file."