The drive might not be formatted or partitioned, that's why it's not showing up. in start>run type diskmgmt.msc and see if the drive is shown there. If yes, then partition and format it. Create one primary partition and use the rest to create an extended partition. Then create logical drives within the extended partition. You will be asked the size, choose the size wisely as per your requirements as once you have put data on the drive you cannot change the partitions without losing data.