My HotKeys work erratically, working when I restart Windows and then after using it for a while, it stops working. I have Window 10 64Bit install and do not have either DropBox nor One Drive (installed but not signed in).
UPDATE: Once I paste the object into the target app, it stops working, restart the app and it works for one screencapture again.
UPDATE: reassigned to own keys and works everytime, so it does seem some app is "taking" the print screen button. Could it be another screen grabbing app installed by the organisation (Snipping tool)?