Newbie! My link to an Url doesn't work!

Hi guys, this is my first flash animation and obviously…it doesn’t work! I need simply to link the banner to an Url, but if I click nothing happend. The strange thing is that if I create a new file and make a button in the same way, it works perfectly. I have created a layer called “link” in the fla file which should work as invisible button. Please help!!!

This is my fla file