Mrs. Doubtfire 2

The first movie was released in 1993, and starred Robin Williams (R.I.P., you great man.) In 2003, Fox hired Bonnie HuntCQ (the mom from Bethoven) to write the sequel. Sadly, Williams fell out of it because of her poor writing. No one can blame him, though, because the plot of the movie included his character following his daughter in college, donning some strange disguise.

Elf 2

The star of the first Elf movie, Will Ferrell, was offered a hefty 29 million dollars to do the sequel. Ferrell turned down the role, however, because he didn’t want to be criticized if the movie wasn’t up to snuff.

Forrest Gump 2

This one is a bit of a stretch because Tom Hanks’s character did everything one can possible do in the first movie. The sequel was in development in early 2000, but Hank didn’t approve because…well…it would basically be a repeat.

I am Legend 2

So the first movie sees Will Smith’s character dying at the end, but that means prequel, right? Well after the movie was such a hit, the prequel was a very real concept until people realized it wasn’t necessary. Idk, I think it could be pretty good.

Wanted 2

Again, the main character dies at the end of the first movie, but that doesn’t mean the show can’t go on. Buuuut here’s the catch: star Angelina Jolie took a pass on the sequel because she thought it was dumb. Pretty blunt there, Ang. Aside from trying to re-incorporate a dead main character, the sequel probably would be pretty stupid.

source: http://www.shortlist.com/entertainment/films/40-sequels-that-never-happened#