I recently bought a new Hitachi HDD and hooked it up to my old computer. The old computer had Windows 8 on it, and so I installed windows 8 on the new HDD as well as I was planning on using it later in a seperate computer. I've now built this seperate computer, but whenever I try to boot up from just the one Hitachi HDD, there's a boot error. It says that I need to use the installation disk because files are missing, but the HDD will boot just fine as long as I have the old HDD from my old computer connected as well.
Why can't I use the Hitachi seperately from the old HDD? I always have to have them both connected, and then wait for windows to ask me what volume to boot from, so I picked Volume 4, which is where my Hitachi HDD is located. It boots up and works perfectly. If I remove the old HDD, suddenly there's installation files missing from the Hitachi and it can't boot.