Problem solved...

[Orenard]

How to get TP-Link TL-WN851ND working on Windows 8.1

Follow the little guide here- http://linustechtips.com/main/topic/154797-tl-wn851nd-on-windows-81/

Then restart your machine!

 

[Orenard]

he turned it off and back on again

Turning it off and back on again was actually part of the process, no surprises there