I have no Idea what happened to the error I had, but now when I try to start my modpack up it wants to start. Like it downloads everything and then it closes out of the launcher as if it were to start minecraft, and then it opens the launcher back up really quick.
I dont know whats going on with that, but I have seen other people have problems with the error part, and it solves itself I think. Mainly when people have the error problem they just leave it alone for a little bit and then it just works after a while. Thats only if you already tried this fix though: That is because you may of named your files incorrectly. make sure that your Minecraft Forge in your bin folder is called "modpack" and make sure it is a .jar file. Also make sure that your modpack is a zip file and is called "modpack" (the file containing all the content).". Thats what I am assuming though.