My computer was working fine until now. I also just ran a chkdsk from the win 7 cd recovery console and the drive worked fine so no problems there. I threw in some more RAM after which this error message began appearing, though I doubt this is the source of the problem. For some reason, the computer just cannot see or boot from the drive anymore. The BIOS sees it perfectly fine. I've ran through all the settings like the boot priority such. No success. Please, I desperately need help with this. This is my work computer and I'm supposed to be meeting with a client tomorrow. I need this problem resolved.