Macbook Air cannot connect to wifi station - Self assigned IP address
Symptoms: Suddenly stopped connecting to a known wifi site (named “X”). When trying to connect, it says that it has connected, but no proper IP address is issued. The airport config shows the message of”Airport has a self-assigned IP address and may not be able to connect to the Internet” Properly shows list of available wifi sites, and is able to connect to all other wifi sites. Tried deleting all relevent pref files and resetting the PRAM, with no effect. Solution: The laptop was banned for some reason to connect to the that particular wifi station. It probably triggered some security filter and caused that particular “Mac” address from connecting to that network. Temporary solution is to change the mac hardware address to a slightly different one.On OS X leopard and on newer machines, the procedure is not as simple as on earlier versions.Typically, just typing in :ifconfig enX ether 00:e2:e3:e4:e5:e6 would work… however on OS X , one must try to connect to a non-existent wifi site and immediately click on cancel, then use the command above to change the mac address . You might need to specify an encrypted non-existent wifi site for this to work (I needed to do that).Once you’ve set your system to another mac address, I was then able to connect to that wifi site.