Can't join Networks
This morning I was connected. Then suddenly, after a couple of hours, my latop will now not connect to ANY wifi networks. It's sees the networks but when I try to manually join one it says "The wifi network ... could not be joined" when I then run diagnostics it says "Wifi not associated" and "review wifi best practices". Not helpful. Can anyone please tell me how to fix it?
It can tether to my iPhone (which is how I'm writing this) via Bluetooth. I'm running Yosemite.
MacBook Air (13-INCH, MID 2011), OS X Mountain Lion (10.8.3)