If resource packs or mods fail to load or cause your game to crash, you will need to uninstall and reinstall them one at a time to find which one is the cause.
Tip: If you know the order in which you installed them, you can uninstall them in reverse order, testing after each uninstall.
Since resource packs and mods are not created by Mojang Studios, we do not offer support for them. If you need further assistance, contact the author of the mod or resource pack.
If this did not solve your issue, see Pink and Black Checkered Boxes Appear Where Textures Should Be.