The mystery remains, but the internets work so I try not to worry about it. It never effected any of the iPhones in the house (iOS 5.1 jailbroken and iOS 6.x not jailbroken) or the other MacBook (10.8.x). The problem then migrated to my iPad2 (iOS 5.x) when it claimed that IP, but the same fix worked there. UPDATE: I fixed this by switching to DHCP with manual IP address and selecting a new IP address. How can this be? What can I do about this? Can anyone recomend a good USB WiFi adapter compatible with OS X? That worked, but was very slow, and stopped working after about 45 minutes of use. I also tried connecting with a cheap USB Wifi dongle. I tried wiping the hard drive and reinstalling a fresh verison of OS X, which didn't help at all. Resetting the PRAM generally solves the problem, but it reapears everytime, sometimes in days, sometimes in a matter of minutes. In the house we have one more mac, a linux box and an assortment of iOS devices, none of which have any problems connecting to the same network via WiFi. I can do FTP transfers (most of the time) and stream music via Spotify (pretty much all of the time.) Everything functions properly when connecting to the same network with an ethernet cable.
Using WiFi I can not load websites in any browser (Chrome, Firefox, Safari) it is as if I am not connected to the computer. Thanks to this excellent music downloader and converter for Mac and Windows, no matter you have free or premium accounts, you are able to freely save and sync all playlists and songs into almost all mobile devices and players. I have a late 2009 Mac Book Pro 13' running 10.6.8.
