MacBook pro is saying "no airport card installed" when I click on the wifi up in the upper right hand corner. Can someone please help??? Thanks in advance! :)

When I attempt to connect to the Internet and I click on the WiFi icon in the upper right hand corner, the drop down states, " No AirPort Card Installed." I did check under "About This Mac>More info> and check to see if AirPort was present and it's there and without any errors next to it like it stated there would be in the Apple help pages. Can someone help me out please??? Thank you so much in advance. :)