When my sister wants to play on the Direwolf20 Modpack Minecraft Version 1.6.4, after a while, it just closes the window without doing anything. She has a Windows 8 HP laptop.
Make sure "Reopen launcher" and "Show console" are checked under the Options on the FTB launcher. Try to open the pack; when it reopen the launcher, go to the console and click "post my log to pastebin.com" and post the link it provides to this thread.
