I just got a preconfigured Macbook Air (with 10.8.3) that refuses to connect to my house WiFi and gives an uninformative "connection timeout" message. The router/modem is working, every other device in house is able to connect using the same network name and password. I verified I was entering the correct password by checking the router admin page.
If there is such a thing as "too many devices" connected a router, I turned off all other network appliances/gadgets at home and tried connecting again with the Air. Still no luck.
I also tried removing com.apple.airport.preferences.plist from /Library/Preferences/SystemConfiguration and restarting as suggested in a MacRumors post. Didn't do anything.
Another bizarre thing is this Macbook Air has no problem connecting to an open WiFi one of my neighbors have (yes, such people exist). I'm using WPA2 and don't want to make my WiFi open.
Has anyone encountered something like this? Also, is there something (preferably command line) tool that will give me more verbose diagnostics about why airport is not connecting?