Unfortunately the Koran instructs Muslims to believe that Mohammad was the Messenger of Allah, and the final prophet.
Koran verse 033.040
YUSUFALI: Muhammad is not the father of any of your men, but (he is) the Messenger of Allah, and the Seal of the Prophets: and Allah has full knowledge of all things.
But if we take a close look at the Islamic scriptures we can see that it was a con right off the bat! The scriptures state that Mohammad was a great man, and an example for all to follow.