achtungbaby.net

This is probably a little late in mentioning (about a year late), but I would strongly recommend against using hacks when it comes to trying to install IE6 and IE7 on the same box (Tredosoft’s hack).  For a couple of reasons:

1. You risk permanently screwing with the Windows Registry, which the Tredosoft hack explicity does.  My co-worker, whom I gleefully recommend the hack to, still has IE6/IE7 issues.  And trying to uninstall the hack or applying provided patches didn’t work for me.
2. The last time I checked, after applying the hack, you need to apply another one to enable conditional comments
3. Bottom line, Microsoft didn’t intend for these two browsers to co-exist

So it’s no surprise that I highly recommend using Microsoft’s Virtual PC. Installing it and then uploading a VPC image of the XP operating system with IE6 will enable you to have an exact replica of that browser, or you could do it the other way around.

You can download all of the stuff here.