I want to dual boot Windows 10 and Ubuntu 14.04.3. I just installed Windows 10 on my 1TB hard drive. No other drives in the machine.
Made an ~400gb unallocated partition of space on the drive. Started Ubuntu installation from a flash drive.
It says that it appears there are no other operating systems on the computer and provides me only with options to completely wipe the drive and install Ubuntu, or do something else (bringing me to a panel from which I can make new partitions and whatnot).
Ubuntu only recognizes my hard drive as 1TB of entirely unallocated space, though it clearly has Windows 10 successfully booting and functioning on half of it.