I have a flash page with 6 button links: HOME   ABOUT   HISTORY   THE CAST   BIOS   GETTICKETS

I have a linke to a page in the middle, a volume off button and a facebook link.

Everything will play fine but when I click on the "BIOS" link and go back to the "HOME" page I get the error message:

TypeError: Error #1009: Cannot access a property or method of a null object reference.

at Untitled_fla::MainTimeline/frame1()

at flash.display::MovieClip/gotoAndStop()

at Untitled_fla::MainTimeline/gohome1()

And I can no longer click on the Facebook page or the link in the middle of the page but the link to "GETTICKETS" work with no problem. Anyone have any idea? My code is below.

stop();

home1.addEventListener(MouseEvent.CLICK, gohome1);

function gohome1 (event:MouseEvent):void{
   gotoAndStop(1);
}

about1.addEventListener(MouseEvent.CLICK, goabout1);

function goabout1 (event:MouseEvent):void{
   gotoAndStop(2);
   SoundMixer.stopAll()
}

history1.addEventListener(MouseEvent.CLICK, gohistory1);

function gohistory1 (event:MouseEvent):void{
   gotoAndStop(3);
   SoundMixer.stopAll()
  
}

cast.addEventListener(MouseEvent.CLICK, gocast);

function gocast (event:MouseEvent):void{
   gotoAndStop(4);
   SoundMixer.stopAll()
}

bios.addEventListener(MouseEvent.CLICK, gobios);

function gobios (event:MouseEvent):void{
   gotoAndStop(5);
   SoundMixer.stopAll()
}

tickets.addEventListener(MouseEvent.CLICK, news);

function news(event:MouseEvent):void{
   var newsLink:URLRequest = new URLRequest("http://www.cnn.com");
   navigateToURL(newsLink, "_blank");
  
}

facebook2.addEventListener(MouseEvent.CLICK,facelook);

function facelook(event:MouseEvent):void{
   var facelookLink:URLRequest = new URLRequest("http://www.facebook.com/");
  
  
   navigateToURL(facelookLink, "_blank");
}

standard.addEventListener(MouseEvent.CLICK, stand);

function stand(event:MouseEvent):void{
   var standLink:URLRequest = new URLRequest("http://www.thestandard.com");

  
    navigateToURL(standLink, "_blank");

}