I am currently unable to install on SketchUp 2018 any of the extensions that I use on a daily basis. This seems to be because SketchUp thinks they are already installed. They are not. The list of Installed extensions in the My Extension page of the Warehouse does not match the actually installed extensions show in the Extension Manager. However, since SketchUp thinks they are installed, I am only shown an “uninstall” button—which doesn’t work because they aren’t actually there, so I just get an error: “The extension could not be uninstalled for an unknown reason.”
This is not a 2018 compatibility issue… most of the extensions are listed under Compatible Extensions, SketchUp simply thinks they are already installed when they are not. It seems to be a bug with the Extension Warehouse itself, and I see no way to refresh or resync what extensions it thinks are installed versus the ones that are actually installed.
Is there any way to completely empty the My Extensions list or to force install extensions from the warehouse?