I have the same issue. There appears to be a bug. I read in another forum that if you use a docking stations (as I do), I should remove my laptop from the dock and try again. Low and behold the buttons worked again. [I redocked and they are currently still working].
MSFT can you please address this bug.
[Edit] . Okay, once redocked buttons fail to work again. - Current (unexceptable) solution, only access files with command buttons 'undocked'.