My computer has been running SO slow. Have tried Bit Defender, Spin Rite, but still running slow. When I bought Win 7 repair, thinking my Windows might be corrupted from some hard reboots due to frozen computer, it only sees D Drive and tells me to download drivers. Not even sure where to find them or why I need them, since my D drive is very small and I never use it. I only use C. Any thoughts on how to get it to see my C drive?