How do I repair or uninstall WMP 12?

Having some grief with WMP 12: plays fine for a while, but after the 4th track it stops responding and then hangs the entire system. Hitting the reset switch only takes me as far the BIOS, which I couldn't understand until I looked at the SATA list and noticed that my primary drive was missing! (only secondary showing, which I use exclusively for back-up). Luckily, a power off/on brings the system disk back into the list and I can then choose to start the system normally

No other programme is causing me the same problem, so I'm thinking that WMP12 may be corrupted. I've looked for it in the programme list to see if I can repair it, or maybe uninstall then reinstall, but it's not on the list.

Any clues where I can find it?

Sys specs:-
Win 7 Home Premium 64-bit (SP1)
G620 (stock speed
4GB (stock speed)
2 x 500GB Sata HDD
Asus P8H61-M LE mobo
Video and audio is onboard (chip and mobo) - no discrete cards installed

Do you have any particular reason to think that WMP is related to the disappearance of your primary drive? I'd worry more about the primary drive visibility than WMP, at least for the time being.

Have you run sfc /scannow from an elevated command prompt?

I think you should look into updating the motherboard BIOS.

The current available BIOS is dated 2012.01.19 and is version 0805

Many thanks for the info. As a last resort I've tried sys restore and the problem seems to be gone (why didn't I try it before?). I could only recreate the problem by running WMP12, nothing else seems to affect the system or make my primary temporarily disappear. I've been running virus, disk and ram tests today and nothing else showed up.

Ignatzatsonic, if it happens again, I'll try sfc / scannow (thanks for that gem, didn't know about it until now).

Shark007, you're right about the BIOS, but the thought still scares me. This is my university pc so I can't risk bricking it during term time (and I'm not sure if it would invalidate the supplier warranty). If the problems keep coming and nothing else resolves it, I might risk it during the summer.