EDIT: Read the above wrong.
You need to go into Disk Management (right click on My Computer and pick Manage). The new drive will appear in the window as being unallocated, you need to right click on the unallocated space and pick New Partition, the defaults are OK but click the "quick format" checkbox. Once this is all complete the drive will show as formatted and "Healthy" at which point it will show in My Computer.