What might cause a strange smell like mold and rotten fruit to come from the AC vents on your 2002 Honda CRV and how could I go about fixing it?

Smelly ACTry draining the freon out of the AC system if you haven't replaced it in a while. sweet odorcould be the start of your heater core going bad and leaking small amounts of coolant that then evaporates from the heat and comes out of the vent.

Stinky Stock Syndrome - occurs when you drive with the recycled air on too much of the time. It causes a mold to grow and your car ac smells like sticky socks or something spoiled or gone bad. Just keep recycled air off as much as possible to prevent this from occuring. If you already have it, you will need to drive without recycled on for ~2wks to clear the smell out. Try spraying Lysol into vents to help clear it out. The dealer won't do anything more than this to fix it.