Is your question about a room? Or are you talking about the closet in a corner of a room?
First, have anything that is closed and never opened is bad as the stale energy builds - then you get stale odors and stuff rooms. Open the closet, air out the entire room and clean the room - closet and all. Let some light into the area, and start using the closet. Closets used for storage must still be kept organized, clean & neat - never use them as a dumping ground. The energy of the home will improve.