Sorry to hear you are not able to connect to Wi-Fi on your MacBook Air. I would be concerned about this too.
I recommend following the steps in the section titled "Symptom: My Mac does not connect to the Internet" in the following article:
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Thank you for using the Apple Support Community. Due to the nature of your issue or question you may find more information by using another one of Apple's support resources - https://expresslane.apple.com/GetproductgroupList.action
Thank you Sheila
I don't need assistance. I need a solution to solve my problem. I can't send the wifi diagnostic if you want.
I would precise that I'm a computer, I tried a lot of things to solve.
Few years ago, after an OS upgrade I had the same problem. I downgraded the wifi card and it worked.
After the 10.8.4 i have the same problem and downgrading the wifi card doesn't solve.
Am I the only one with this problem ?
I'm having issues with my wifi after updating my mid 2010 macbook pro to 10.8.4, but it's not exactly the same. I can connect to my router most of the time, but then I'll have really long load times and dropped requests, sometimes losing my connection completely. It's really frustrating. I've tried several things to fix it, but nothing has worked so far. It worked fine before upgrading to 10.8.4.
I bought my macbookair mid 2009 with snow leopard. When I upgraded to Lion, I lost wifi. I fixed it on Lion when I downgraded my wifi card. It could maybe solve your problem.
On my computer, with the 10.8.4 the downgrade doesn't work. It only works till 10.8.3
And I never found a solution with Apple Support...They don't answer or they say to call and to send your computer and of course... to pay, instead of fixing this bug.