RazerJDog

Hey so i'm trying to launch the pixelspark modpack. And for whatever reason minecraft itself won't fully load and open. the window pops up in my taskbar, but it's just a white screen and it won't pop up when i click on it. The same thing happened for all of the other modpacks i've launched. Hexxit is the only one that i'm able to play and see the main menu screen. any advice on how to fix this?