how to install windows seven and keep all files.

My friend is trying to upgrade to windows seven from windows vista now first he would like to know how can he install windows seven without losing any of his files that he has now? and second whats the difference between buying an upgrade version of windows seven and just buying a version of windows seven that does not say upgrade on the box

This tutorial should show you how to carry out an upgrade install of Windows 7 and will allow you to keep personal files.

http://www.sevenforums.com/tutorials/1818-upgrade-install-windows-7-a.html

An upgrade disc will look for a previous installation of Windows and will do what it says i.e. upgrade the operating system to Windows 7.

A regular retail disc needs no qualifying software and allows you to carry out a clean install of Windows 7, but it means you lose anthing you haven't backed and re-installing all your applications.