Has anyone had any problems where a website behaves differently with Microsoft Internet Explorer 10? I got a call from someone who said that he could not use a drop-down window on a web page I manage after he upgraded to Internet Explorer 10 and he did not have any problems before. If my memory serves me, it is not possible to have two versions of IE on a computer (which is what I would like to do to test this). Is that right? Also, is it possible to uninstall and reinstall Internet Explorer? It is an ASP.NET application. In order for me to debug what is going on, I will have to recreate the error. Currently, I do not have IE 10 on my computer. I have IE 9 and I cannot recreate the error with IE 9. I am currently in the middle of another project. So this is why I need to know if I can have two versions of the browser on my computer at the same time. I think this might be Microsoft's way of making people move from ASP.NET and SILVERLIGHT to HTML5.