Well, I'd say "beaten to it", but twice? Man, I'm losing my touch . +2 - if it shows up in diskpart, it simply hasn't been initialized for use on that machine, and disk management (diskmgmt.msc if you want to run it directly from the start menu or run box) should be sufficient, as previously mentioned (twice).
My Computer
At a glance
Windows 10 Pro x64Intel Core i7 4790K @ 4.5GHz32GB DDR3Nvidia GeForce GTX970