Hello my name is AllenMCStudios and I have been having the same problems since October but didn't have a chance to post this so anyways I tried 1.7.10 and it worked for a day I come back it won't even launch so I download 1.6.4 and that didn't work then 1.8 came out with forge and it did the same thing let me give you the Output Log and I might try to get the old ones first is the one from the 1.8 of forge
here is the 1.7.10 one
please reply as soon as possible