If this 540S is new and has never been initialized, then it won't show up in Windows until it has been initialized. To initialize it, you must run the Disk Management Control Panel applet. Right-click on the Start button and select Run. Enter the command "diskmgmt.msc". When this applet starts, it will see the new drive and start the initialization process automatically.
Hope this helps,
Thanks, that did it! It didn't actually start the initialization process automatically, but the new drive showed up as "Unallocated". I right-clicked on this and was then able to proceed with checking the drive, and assigning it a letter. Now I have my Terabyte, which is awesome!
Good to hear. Enjoy your NUC - and your data drive.