It means you have install game incorrect. The installation is the big problem. But you dont worry. Download the fresh Nfs mw from http://gamesblog.tk in blog section at the categories in full games . In this site this game is requested. and the site administrator upload that . You find that it is only in 368 MB and works . Hope this game work for you .
It works for me .Thank You
You as a member should know that piracy is not allowed on this forum.
To the OP:
We cannot offer help on pirated/ illegit games here as it is against the forum rules. You should buy the original. Like Gman450 said, the game being pretty old, shouldn't cost you much.