Windows 8 won't boot

Hello, I have had a solid state drive for a few weeks now which I have installed windows on, as well as my original HDD. I booted into my old drive today to get some old files and when I rebooted onto my solid state again all I got was a black screen with a small white line (an underscore) blinking in the top left corner. (This happens after the initial bios part). I did some troubleshooting and determined that it was not hardware related because i was able to access the solid state and all of its files when I booted windows on the original HDD. I can't seem to be able to get to the windows repair screen or anything else. Any thoughts?