I bought a white scroll a while back and applied it to my sword, after trying to apply a custom enchant to the sword the enchant failed and attempted to break the sword at which point the protection stopped. However, after that the protection on the sword disappeared. I am unsure of whether the protection has fully disappeared or if the enchant just doesn't show on the sword. I have already reported this but since nothing has been done I decided to also report it on the forums. The sword still currently has no protection on it and I have not attempted to add an enchantment since then.