Internet connection problem

Hello, i am trying to connect to the internet with my wireless router. it was working fine yesterday. I called my internet proveder n everything is ok there, so i called netgear and everything is ok there. they both said that there is something in the computer that has been turned off on the computer so it wont pick up the wireless signal, when i called my computer company they said they know what the problem is n they would tell me what to do for 60$ :( please help me