Take a gander over to Disk Management, in the lower graphical section, and report how it is listed.
There are actually two components to this section, the Disk section on the left, and the Volume section on the right.
You should see on the left, Disk 1, or 2, Basic Disk, Online. If it says Foreign, then right click like Plumble said, and Import. This may well be the problem since it was an external USB? cabled drive on a prior computer.
On the right side, it should say NTFS, list the volume size, have a drive letter designation, and "friendly name". If it had been previously actively asigned a letter, that would be the same as the SSD, or another attached HDD or DVD or CD drive, it wouldln't show up properly. There you can also right click and assign it a letter, like "F" or "V" or any non used letter so the OS can ID it properly.
Hopefully that will get your OS talking to your secondary HDD.