So I do know this is an older article but I just wanted to say you are spot on. I have a nightmare of a story regarding: The Apple Store, My New MBP, The Airport Card and 3 Replacement MBP. Now I've had this one for a while now and all of a sudden the Airport Card cannot be found but Bluetooth works just fine? I went forward with those instructions and my Airport Card will no be dislodged ever again.
My MacBook Pro from 2009 was having the same issue of not finding the Airport Card. I had it replaced and still no joy. I ended up buying a new MBP and didn't put much thought into the old one. I recently went back to play with it and see if it was in fact the driver and it was fixed in Mavericks. After the upgrade and reset of PRAM/SCM etc wireless still not working just via ethernet cable.
I decided to buy a micro USB wireless adapter from Amazon for like $25. It just came in the mail today. I downloaded the driver and utility, installed and restarted the laptop.....bam the Airport Card was recognized and is working perfectly!
Could be a coincidence or it could be a possible solution. Just putting it out there. Driver was for a Bolse BO-N1557 Wireless USB Adapter. Worst case scenario I have the Wireless USB Adaptor as a backup.
I had this problem pop up one summer afternoon right when I entered the Studio, it raised its ugly No wireless hardware found. head. To fix it reset the P Ram by holding Control> option> P>R
restart laptop. If that doesnt work. Reset SMC . If that doesnt work see a Genius Bar. It may a real problem. Air card down/cable loose etc.
Thank you so much for sharing your solution!
The post-it trick seems to have worked in my case too! The constantly failing wi-fi was driving me mad! I tried every single "fix" I would find out there, and nothing worked for me. I was a bit desperate and was about to buy a new antenna... But it seems that the issue was actually there, in the connection of the cable to the motherboard, and putting some extra pressure there did its job.