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Running multiple versions of IE on the same machine

Installing a version of Internet Explorer, in general, will result in the loss of the previous version. While this is in fact a good thing in terms of consistency it makes for debugging on different browsers that bit more difficult.

There are several solutions to this problem. Multiple PCs all running different versions is the most obvious and while not the most practical would provide with the most ideal environment. Failing that, several versions of Virtual PC (or equivalent) running on the same machine each with a separate version of Internet Explorer installed. This would, at least, keep each install separate however would require a fairly powerful machine to run 3 or more Virtual PC applications at once.

If neither of these options are suitable or even practical then there is one final option, and that is to install 'stand alone' versions of Internet Explorer. First documented when IE6 was being updated due to a lawsuit it was soon recognised that, with some minor tweaking, several copies of IE could live side by side on the one PC. While each version is not entirely independent, it certainly provides a stable enough environment in which to do testing. The following URLs should provide you with enough information to get multiple versions running on your PC.