Minecraft Forums

I made a forge modpack that is basically set up to replace the entire .minecraft folder. This worked completely fine for my computer as well as my friend's, but when I try it on my other friend's mac he launches the game, the forge loader shows up and everything seems to be fine, then it gets stuck on a black screen. What do you guys think is the problem? His mac has played modded versions before it's just weird its not working this time.