Believe it or not, some people are still on IE6?!? Yeah, the diehards still can’t give it up – even though it’s riddled with issues. If you’re a developer, you need to make sure that your site works well with older browsers, specifically, IE6. Try downloading Multiple_IE, from tredsoft.
This installs IE 3, 4, 5, 5.5, and 6 on your machine regardless of whether you have updated to IE7.