Question: Can I upgrade my existing Windows installation to Windows Vista, or do I have to back up my data and reinstall from scratch?

Answer: Whether or not you perform an in-place upgrade (where Vista replaces your existing operating system, but leaves your current files and installed programs in place), you should back up your data first. You can always perform a clean installation (where you begin by wiping the hard-disk partition and its contents clean). This is often the best choice–first because it may be faster than upgrading (even if you include restoring data files and reinstalling applications), and second because it minimizes problems and conflicts stemming from old applications and drivers. In-place upgrades may be more convenient, but you can’t upgrade every existing Windows version in-place. Our feature article ” Everything You Need to Know About Windows Vista ” includes a chart that lists which versions can be upgraded in place .

Source: PC World