recently my imac has been connecting to a neighbor's unprotected wireless network instead of connecting to my airport. Is there a way I can make it connect to mine? My internet service is faster so I would definitely prefer to be using mine! I've tried going through "network preferences" and haven't found a way to successfully manually select which network to join. It looks like his router's signal is the strongest one being found and so my imac will join that network. This has only been going on for a few days and I haven't changed anything in my set-up recently. What can I do to get it back to using my own wireless router?