I had a machine with Windows 2000 loaded on it and I had to purchase the professional version of JAWS because it would not run properly on that machine. I am now running JAWS Professional with my computer because of that little problem. On the other hand you do not have to uninstall 5.0 to put 7 on your computer. I always install new versions of JAWS over the top of my current version that way if I don't like the upgraded version in a particular application I can switch back and forth to the different versions of JAWS. Alicia