For the last five years I have been using virtual machines to test my installations. It is by far the best method. If you are not using virtual machines to test, you are missing out.
With virtual machines, you can set up different Windows operating systems and configure them according to your wishes. At a minimum, you need one virtual machine for each supported version of Windows that your product runs on. The virtual machines are saved on your hard drive and you can use them whenever you want.
Perhaps the biggest advantage is that you can run a virtual machine, test your installation, and then discard the changes when you’re done. So, each time you boot up the virtual machine, it is still in its “clean machine” state.
To get started using virtual machines, you can use Microsoft Virtual PC. I have used this for five years and have found it to be really nice. Plus it’s free. You can download it from the Microsoft website.
VMWare Workstation is also available, but it costs $100 to $200. I have never used it before, but a lot of people say it’s the best virtualization platform out there.
Regardless of which one you choose, make sure you use virtual machines in your testing.