Code not working >.<

Hello Gents..(use the term loosely lol) ok so heres the question i tried to see in prev. forum related topics but did not find it...Can anyone explain to me wtf is going on with my product Key for this game???? i did not pirate it (i do not believe in that,,oo) but when i was going on-line so i could save my progress and not have to see the opening creds every time ..UGH it stated my code was invalid. it has taken me 2 days to download it and get it running somewhat 1/2 ass on XPSP3... (the game not the mod LCPD FR) ...and now this and now Mico wants me to buy a code..I JUST bought this game. UGH. so anyone? im so gettin over this...but i do want to get into this LCPD FR the only reason i bout GTA IV..jus seems always glitches and hic-ups with Microsoft...now Rock Star...this is why i quit flying MSXFS.. thanks in advance  PS: can you save the game when your playing off line? for a start point and not have to view the opening creds?...but i do wana play LCPD FR  online. Thanks again. ~Ficdawg