Messages

I seem to be having trouble, I followed the proper install instructs to the T and still have problems, I tried with a fresh download of the game as well as the modpack. when i start the game i check the mods and mark them all for usage. when i close the mod screen they wont apply. apon reentering the mod page, they are all unchecked again. when I checked the mod config that had to replace the old config files. it has been changed automatically to only consist of the core file. I dont understand what is going wrong. please respond or email me if you can help.