Wifi won't turn on since upgrade to Lion

I finally made it to a genius bar. Having reviewed the history and reflecting on the fact that the logic board is the only bit of kit that hasn't been changed they have elected to change that on the nvidea ticket (mine is a lap top with the duff nvidea chip) as it seems likely the wifi card drop out is connected to that. All very helpful as ever, and I pick it up tomorrow. Fingers crossed.

Hi wasteofspace ... did your new video card fix the issue?

Like everyone else on this thread, I have a late '08 MBP. When I upgrade from Leopard to Snow Leopard, my AirPort card stopped working -- but only when something (monitor) was connected to the DisplayPort. After hours with Apple engineers, a subsequent release of SL fixed the issue.

I've only just now upgraded to Lion, and now the issue is back. I wonder how many folks in this thread were using external monitors through the DisplayPort without realizing that was the issue...

Here's what worked for me....

1) open System Preferences

2) open network preferences

3) turn off show wifi status in the menu bar

4) remove wifi from the network source menu (highlight wifi & click "-" at the bottom of the menu)

5) remove external power & battery and reset SMC by holding power button for 5 seconds

6) replace battery & external power then restart

7) open system preferences

8) open Network preferences

9) add wifi to the source menu (click "+" at the bottom of the menu and add wifi)

10) turn wifi on....TaDah (hopefully)

THANK YOU !

Hi. Sorry about the delay in posting a response. I was waiting to see if the fix worked......it does.

I have to say that frustrating as the problem was it, Apple couldn't have done more to help and in particular replacing my lap top Johnny Cash style. I.e. 'one piece at a time'

This worked for me as well. Sounded too good to be true but it did the trick.

Thanks!

Hi - I just got the logic board replaced by Apple on my late 2008 MBP 17". Since then I've started having the following WiFi issue:

At first everything works fine, it connects to my network and internet is perfect. Then after maybe 45 minutes (can be longer) the connection will die - can no longer load web pages. In the status bar the wifi is still strong, and if I click on it then it shows still connected to the network. So then I try turning it off and on again, and it turns off but won't turn on again. I open it in Network prefs, it shows WiFi off and pushing on won't change anything.

This can be solved by a restart, which gives me internet again for another 45 mins then same problem.

Thinking that the new wifi card (which is on the logic board, right?) might be missing a firmware update, I went back to Lion 10.7.1 (I was on 10.7.4), and then did a combined Mac OS update through software update. I have also tried the solution proposed by jibguy above.

This is EXACTLY my issue! Apple even took my laptop for a week and tested everything and said "they couldn't recreate the issue" please let me know if you find a solution!!!

Same issue as mine? Did you get a replacement logic board too?

Actually, yes I did! I got my logic board replaced after mine spazzed out. Wifi worked for 4 days and then this freaking issue started happening

What model + specs?

Not sure how to figure that out. Not that tech savvy but the best I can tell you is whats on the sheet of paper they gave me: Main Logic Board 2.66Ghz

go to the apple logo on the top left of the screen, click it and select about my mac... it should say 2.66Ghz then the name of the processor.

How old is the computer? It should say on the top right of the paper they gave you - MacBook Pro and then the year

2.66 GHz Intel Core i7 and it's mid 2010.

Do you sometimes turn on your laptop and it says Wi-Fi: No Hardware Installed?

Mine is a 2008, no I don't get the No Hardware thing, weird.