Attention regardez bien ce qui sera possible de faire selon votre OS Actuel
Non Supportés :
· Windows 95, Windows 98, Windows Millennium Edition, Windows XP, Windows Vista® RTM, Windows Vista Starter, Windows 7 M3, Windows 7 Beta, Windows 7 RC, or Windows 7 IDS
· Upgrades from Windows Vista to Windows N, Windows K, Windows KN, or Windows E are not supported.
· Cross-build type in-place upgrades (for example, fre to chk) are not supported.
· Pre-release in-place upgrades across milestones (for example, Windows 7 RC to Windows 7 RTM) are not supported.
Lire le sujet dans le détail ici :
http://blogs.technet.com/longhorn/archi ... tions.aspx
Et la doc MS ici : http://www.microsoft.com/downloads/details.aspx?familyid=E170EBA1-5BAB-401F-BBF5-00F0EE7FE0FB&displaylang=en