Windows .jar Help please

[locy333]

i can open the launcher fine but when i try play any of the mod packs it wont work... the game window goes small and i basically crashes... i cant find anything to help, i tried downgrading and updating java and stuff...
when ultimate ftb came out i could play that for a bit but today it crashed in the menu and wont work any more, i can post screenshots if that helps. please help D:

 

[Nerixel]

Can you please post the crash report and console log to pastebin and provide the link?

 

[locy333]

http://pastebin.com/YV6TSrYG

this is a different issue, when i click play the window just freezes and the buttons fade out

 

[Nerixel]

Try deleting the instance folder and redownloading.

Back up any saves you have and add them in after it starts working.

 

[locy333]

I've tried that

 

[Nerixel]

That's what worked for me when I had that problem, so I can no longer help.

 

[locy333]

Well I guess ill try that again, thanks

 

[Booker The Geek]

Can you post a new console log please?