IE won't let a tooltip script work properly.

IE won't let a tooltip script work properly.

I just spent several hours figuring out how to make a mouseover script put up a larger image when the cursor moved over a smaller image. I learned  how to do it all, using Firefox, Safari, Chrome, Opera and you name it. Then I checked it in IE8 and it would not work. It somewhat works on line, but when downloaded, all the others work it, but IE just fails.

Of course, I should have thought of that to begin with...but hope springs eternal...

I got it at this site: It seems a wonderfully simple piece of work.

http://cssglobe.com/lab/tooltip/02/

What possible extra code could IE need to behave like anyone else?