Launcher Isn't working properly

[AlextheGreatone1]

Ok, Tekkit launcher launches and seems fine until I launch a Modpack, any modpack, The Launcher Goes away for a minute or so, then reappears with no Minecraft. There is no error in the Console, I've tried Many things. I've updated And installed Java 64 bit, increased the memory used & updated the java version, I have Completely Reinstalled tekkit, gotten rid of my firewall & anti-virus, I would be happy To Provide anything needed to fix this. 

As i sit here and listen to my friends playing modpacks ;-;

[TwIStology]

I don't generally have an answer, But the entire launcher won't accept my fucking password overall. I have used my email, and my username, with the right password. 

Quoted : "Invalid Credintials" 

Too bad for invalid, I've tried everything. I have changed and reset my minecraft and mojang passwords countless times. And it still hasn't came up as correct "Credintials"