When someone wants to come over, the game freezes at the saving screen, and then presents a "You are disconnected from Nintendo WFC" screen and resets.
Is it with one specific person? Or anyone that tries to come over? It may be their connection, if its just one. If its everyone, its probably yours, get closer to your router.
oh, dont turn your firewall off, itl open your whole network up to all kinds of nasties...
take it from the one with the experience of it...
(i still shiver at the thought...)
hmm.......when I connect over wifi I move closer to the router and use a different tv closer to the router! Seems to work more efficiently! However I could never wifi with anyone on the D.S. it never worked!