I know there's a lot of these threads around, but none of them really explain my problem or fix it. I installed forge on one computer, and forge worked once. I closed the client, and now it just black screens after popping up and setting everything up. I'm not sure what happened or why. I was wondering if anyone can help me.
EDIT: I tried to...
-Update Java
-Using latest Forge
-Using latest Minecraft
-I downloaded the universal RAR, and put those contents into minecraft.jar