If the dreamer is a woman, dreaming of a witch could represent her own senex, or that part of her psyche that is older and wiser.
Thus any message that she receives from the witch is important, and should be written down immediately upon awakening.
If the dreamer is a man, he needs to take a good, long, honest look at his attitude toward women. He may be caught up in the notion that all women are out to get him.
If the witch is friendly in the dream, whether the dreamer is a man or a woman, it augurs an increased social life.
If the witch is the ominous Halloween figure, rough times in romance lie ahead.