Forticlient install fails with error There is nothing to install

I had the same issue on Macbook. But it was not a new installation and previous attempt of the same version was not completely cleaned up on the drive.

I haven't experienced it with Windows so I didn't have to do complete cleanup. But looks like "regedit" seems to be a good tool to do that (ignore any advertisement to sell software below):

https://www.totaluninstaller.com/program-uninstall-center/how-to-perfectly-uninstall-forticlient-on-windows/