Hello,
I have the acer E5-573 , i bought it recently and i also got an external hard drive with a 3.0 cable .
the thing thats bugging me is it wont work when i plug it in the usb 2.0 port and i cant figure out why , i have been searching all day and ive also unchecked ' allow computer to turn off to save power ' in the properties tab in device manager and it wont work.. ive charged my phone + used flashdrives and this external hard drive wont work .
it does work when i use the 3.0 port, maybe it doesnt have enough power?? i dont know . 
maybe someone can help me..thanks