If you order a windows server OS with extra drives and don’t see your extra drives (fig 1.) in the server follow the steps below:
1. Right click on the windows logo at the bottom left of the screen and select disk manager:
2. You will see the second drive or how many drives you have added to the server in an offline condition. Right click on the drive and press Online button:
3. The disk will then be not initialized. Right click on the drive and press Initialize Disk button:
4. Select the partition table for your drive default is MBR for bigger than 2TB drives it will be GPT:
5. You can now add a new volume for the drive. See the pictures below:
6. After all of these steps you should see a similar picture and your other drives in the server.