I had the same problem.

Have you been mucking around in your BIOS recently?

CACHEING and SHADOWING can improve the performance of your PC, but P2P programs have issues with CACHEING and SHADOWING which can cause your PC to crash.

Try checking your BIOS ('DEL' while booting PC),

and then poke though every menu you see,
disabling any instances of CACHING and SHADOWING.

'F10' to save and exit.