Board Thread:Help!/@comment-25158222-20140709134836/@comment-25148944-20140709145252

Pretty sure the cause of that is the option to make a Corruption or Crimson world in the World Creation menu inside the game. The NTerraria Server doesn't have that option so it sticks to the default option which is the Corruption. If you want a Crimson World, you'll have to create it in-game