If you check your crash report on your CMD console or whatever it should show you some text under "A detailed walkthrough of the error, its code path and all known details is as follows" and it should mention some mods it had trouble running. Whatever mods it listed on there are messing with your game, or other mods therefore not allowing you to launch. Delete them for a quick fix or try to reinstall them on the right version of forge your using. It could also be that the mods listed under there are not compatible in any form.
I've been looking at my run.bat file in my server files and I don't see an option or text rather which states how much RAM my server uses, I've been trying to increase it's usage and I've had no luck. Help?