Used the mod browser.you're using the modbrowser or you've downloaded and installed it manually ?
edit : if it doesn't change after uninstalling the mod, you may try to delete the content of the cache folder in "My Documents\My Games\Sid Meier's Civilization 5\cache"
It's strange because I've turned it off before with no problem.
The only thing I did differently this time was load a saved game that I was using the mod with, after I disabled the mod.