Why wont this load with firefox but load with IE?

%26lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-...

in IE, my javascript iframe is shown when a user clicks a button. In firefox, however, it does not show. When I delete the above code, the iframe shows, but some of the fonts become larger. How do I fix this??

Why wont this load with firefox but load with IE?windows xp sp2

You won't get any good answers with just the header posted!

If you share the url, thousands of people can look at it and give reasonable advice. I am one of those thousands.

Why wont this load with firefox but load with IE?microsoft sql server internet explorer

some things are only compatible with certain browsers
You need to change the script settings in FireFox.
I'm assuming you make websites, so hopefully you know to have javascript enabled in firefox, right?
If removing the doctype statement lets the iframe load, I'd suspect there is something in your code that isn't proper xhtml. It's not unusual for one browser to parse bad code that another will reject. Try running your code through a validator.