3.52 M33 - Metal Gear Solid Disc 1 POPS error (80000004)

Hi, i searched this forum and google for the answer to my problem but i cant seem to find a solution.
Every time i try to play disc one it gives me a "game cannot be started (80000004)" error. Disc 2 loads fine though.
Can someone help me please.

My firmware = 3.52 M33-4 if that helps.

check your save-game folder to make sure you've not loaded a different version of the game (slus/slps etc. code), took me ages to figure that one out :P for some reason it doesnt load if you have a save-game from another code