With the pickaxe equipped, trying to bring up the datapad with any hotkey results in the datapad getting activated but not actually appearing, and the pickaxe remaining equpped. If you "open" the inventory screen by hitting "i", you can hear the clicks that accompany the movement of the selection and you can use/drop items all the while the datapad is not visible (and the pickaxe is). Hitting "e" from this state puts away both the invisible datapad and the visible pickaxe, and then the datapad will work correctly. Instead of this, I'd expect the pickaxe to be unequipped and the datapad opened when a datapad hotkey is used.
Equipping the pickaxe then hitting "e" will put the pickaxe away, this likely is the intended way to unequip it.
Customer support service by UserEcho