Blizzard made a new account verification system which checks game locale and sc2 account locale, if they don't match game will not login to battle.net.
Example: You have an English account, but the game is German. You will not be able to play on battle net.
Solution: Open ProductLocale.txt from Mods\Core.SC2Mod\Base.SC2Data mpq archive (use MPQEdit for that) and replace the string value with the required one.
Example: change deDE to enUS
Example: You have an English account, but the game is German. You will not be able to play on battle net.
Solution: Open ProductLocale.txt from Mods\Core.SC2Mod\Base.SC2Data mpq archive (use MPQEdit for that) and replace the string value with the required one.
Example: change deDE to enUS