Having multiple versions of Internet Explorer installed in parallel and running concomitantly on the same Windows operating system is not a scenario supported by Microsoft. It's just one flavor of IE at a time, as far as the Redmond giant is concerned, and while this might bide well with end users who are encouraged to tap the benefits of the latest Internet Explorer iteration, the same cannot be said for developers and designers. This simply because the development process involves testing web content in all possible browser versions, and Microsoft has certainly not made this an easy task with IE. However, a solution is now available: it bundles the rendering and javascript engines of IE8 Beta 1, IE7, IE6, IE5.5 into a single product.

"IETester is a free WebBrowser that allows you to have the rendering and javascript engines of IE8 beta 1, IE7 IE 6 and IE5.5 on Vista and XP, as well as the installed IE in the same process," reads the description of IETester 0.2.2, a tool put together by Jean-Fabrice Rabaute, known for his work on the DebugBar debugger for Internet Explorer. Sure enough, IETester comes to provide a way for developers to test their content across multiple IE variants on the same Windows, without turning to registry hacks or virtualization solutions.

IETester 0.2.2 is still in Alpha stage, and as such comes with a set of inherent problems, that Rabaute plans to address in the following releases. But even in this early stage, IETester promises a lot, as far as IE 8 beta, IE 7, IE 6, IE 5.5 testing goes. The tool features Microsoft's Fluent/Ribbon graphical user interface, introduced with the Office 2007 System, and is designed to incorporate basic browser functionality, including the pervasive buttons associated with navigation from Back and Forward, to Refresh and Stop. With IETester, the testing process is streamlined to a maximum, as the solution offers tabbed capabilities, permitting developers to open a website into various versions of Internet Explorer 8 across multiple tabs.

IETester 0.2.2 can be downloaded from here.
Internet Explorer 8 (IE8) Beta 1 is available for download here.