So, I came home today and got the error message that my desktop could not be found. Instantly I remembered the time my HDD with the desktop got unplugged. So, I restarted my PC and it wouldn't startup until I unplugged my WD20EARX HDD that I recently (2 months ago) purchased. This is (obviously) is the drive with my desktop on it. I put it there because I am running my OS from a 120GB SSD (agility 3). I tried checking the SATA connection and even swapping to a different SATA connection... and even a different SATA controller on my motherboard. The drive always powers up and I can hear/feel it spinning like a normal drive should. But it's not recognized by either the OS or my motherboard. I also tried plugging it into the base station of an external Seagate GoFlex external drive.