If you want to upgrade from your current Windows version to Vista, you may be able to buy and qualify for an upgrade, but installing that upgrade may require a clean installation.

An “in place upgrade“ means you can install Windows Vista and retain your applications, files, and settings as they were in your previous edition of Windows. If an in place upgrade is not supported, you must perform a “clean install” which means you need to wipe out your current system in order to install Vista. To save your files, you need to copy them elsewhere and can make use of the provided “Windows Easy Transfer” to help copy all files and settings, but you will still need to reinstall applications after Vista is installed.

C = Clean Install Required
U = In-place Upgrade Supported

If it is not immediately apparent, the big problem here is that quite a few “home systems” have XP Professional installed simply because that is what their last computer came with. It will be some unhappy customers who find that in order to install their new copy of Vista Home Premium, they will have to start fresh and loose all their current settings, files and applications.

Click here for a list of what is missing from the different editions