If you ever come across the following error on the partition screen while going through the installer for Windows Server 2012, Windows 8, or Hyper-V Server:
The simple fix that worked for me was to disable S.M.A.R.T. in the BIOS. If that does not work, you can also try deleting all partitions, click on New and create a single large partition, reboot, then try that same partition.
Hopefully either one of those work for you. Comment below and let me know if it resolves your issue or if you find any other fixes!