Internet explorer says Object doesn't support this property or method

Question

This line is 79:

window.addEvent(\'domready\', function(){     
    mySlide = new Fx.Slide(\'advert\');
    mySlide.hide();
});

It also doe

Answer 1

In case you are landing on this page while desperately searching for why you have this error in IE, allow me to point out another way this can happen. Hopefully, either the mere act of me posting this will help me remember this, or this question will show up in google the next time I run into this error. It seems to happen at least every 2 years.

This can show up if you've named a variable (Not sure if it has to be global, mine was this time) the same thing as an element's ID. For instance: