That's quite weird.
Also, are you using a cracked (illegal) copy of Warcraft 3? Or the retail version? The site doesn't allow piracy, so I can't help.
Don't be too stingy. If you have a CD-Key from the past, just add to your Battle.net account and get the latest patch. There's still a few days left for this method. Otherwise, buy a game (it's not so expensive).