My wife reminded me sometimes it wont work if other network connections like Local Area Connections are active.. she says to disable all connections before you hit the troubleshooter.
OR
Try this.. I just found out its the best quick fix.. quicker than my post above.
Go to the Network Connections icon in the task bar ( it's the icon with all the little bars) and use the slider on Airplane mode to turn wireless back on. It's that simple.
I still have a need to disable that button because I accidentally hit it now and then and it's annoying. Plus many games and apps that want to map to the F12 key can't do it because of this airplane mode function. That's part of Windows 8 mobile features But
many desktop users don't need or want a lot of the mobile features in a desktop OS.
The first poster said, " I just upgraded my 64 bit HP Pavilion g7 2010 nr to windows 8. now, whenever i try to use the wireless button (Fn + F12) it changes the airplane mode instead of wifi."
But this is really not the case. Airplane mode IS wifi.. and every other wifi connected device in your system.. it turns them all off quickly so you can be protected at airports and on the airplanes.. hence the name Airplane Mode. It makes sure Wifi and all
other devices that are able to connect to any network absolutely cannot run. At least thats my understanding of this silly feature. Well, perhaps not silly if you need it but most desktop users don't.
I have a HP Pavilion G7 laptop I use as a desktop machine. I don't know if this is a Microsoft blunder or HP or a combo of both but I wish they would give you the option to disable the functionality of F12 as it is now.
From Control Panel, Windows Mobility Center does have a way to change the functionality of the F12 button but like me, this feature does not show up in Windows Mobility Center for some unknown reason. Look here: http://windows.microsoft.com/en-US/windows7/Using-Windows-Mobility-Center