I was watching a string of "100% fix" Youtube videos about this error (each one said, "if this didn't fix try this next video"
). One of the things mentioned in the vids was that the error could be caused by 32-bit vs 64-bit compatibility issues. AFAIK MW2 is a 32-bit application. Since you're on 64-bit Windows 8 it might be trying to use/load 64-bit dlls. Have you tried various compatibility options (right click > properties > compatibility)?