I have a 3rd or 4th generation Ipod touch that my daughter gave me ....the wifi is grayed out. I tried to reset my wifi box already and it didnt change a damned thing ..still greyed out.. will someone pleae wave their magic wandxfor me and change this pumpkin for the ball already?? Lol..please. if i take it to an apple store they will replace it fir REAL?? Its never been wet or anything. But it was my dauhters, ya know? I dont have no way of getting the reciept at all.

SOURCE: wifi grey area

Here is a way that solved the problem for me.
Downgrade the ipod touch to firmware 1.1.4. You have to put your ipod into DFU mode ('not recovery mode) and you have to have an itunes version that supports this old firmware. 7.5 oder 7.7 i think.
to load your own firmware you simply hold the shift-button while you push the restore button.

After you have firmware 1.1.4 on your ipod touch, download the jailbreaker "Ziphone". This programm has the option to fix the "no Wifi" problem. Look in the advanced options.
In my case, this was the only thing that solved the problem. I tried restoring it often but nothing worked.
After Ziphone fixed your Problem, you can update the Touch to the latest firmware. Wifi was still working, at least for me