HT4628: Wi-Fi: How to troubleshoot Wi-Fi connectivityLearn about Wi-Fi: How to troubleshoot Wi-Fi connectivity
Currently Being ModeratedApr 9, 2012 8:32 PM (in response to Foto7)
Unfortunately, there are 2 main reasons for this message:
1) The AirPort card has failed and will need to be replaced
2) The AirPort card is not making good electrical contact in the socket where it is installed
In either case, this is a job for a service shop, so you should take it to an Apple Store....if you have one in your area....or contact Apple Support directly for options and instructions.
Currently Being ModeratedMay 1, 2012 9:35 AM (in response to Bob Timmons)
What did it for me after everything else (SMC, PRAM reset) failed was to reinstall my system using the original disks that came with my computer. Back up your important stuff first, of course.