Is it raw or partitioned? To check go to:Control Panel -> Administrative Tools -> Computer ManagementChoose "Disk Management" under the "Storage" header on the left.Check what it says under the "File System" heading for your new drive. (If the drive isn't there at all, then it's something else)If it's blank, either Windows doesn't recognize the partition type (ex. Mac OS partition), or it is a raw drive (no partition).If you know there is nothing on the drive, you can format it with an NTFS by:1) Right click drive in list2) Hit "Format"3) If an alert pops up, hit "Yes"4) Give it a name (Volume Label), Set the "File System" to NTFS, and leave the "Allocation Unit Size" at "Default".5) Hit Ok.6) The drive should format, it should now show up in "My Computer".