My Devices and Printers windows is empty and a green progress bar goes in address bar always. This issue mentioned many times here and the only worked workaround is turning on the "Bluetooth support service". That doesn't work for me
and I tried many other methods such as restoring from a save-point, uninstalling many programs, and nothing works. Then I create a new user this time and logged off my current user and switched into the new one. ALL THINGS WORK WELL ! Devices and Printers displayed all hardwares rightly! So, I switched into the old account, ALL THINGS WORK AGAIN!
Maybe my experience is useful for others. Good luck for all of you.