Si jamais une clé de type "OEM" ne fonctionne plus après réinstall...

SLIC licensing.

Grab a copy of the OEM certificate. C:\Windows\system32\OEM\oem-cert.xrm-ms. Find your OEM key, mine is HP, so 74T2M-DKDBC-788W3-H689G-6P6GT for Windows 7.

On new system, install the key.

cscript "%Windir%\System32\slmgr.vbs" -ipk 74T2M-DKDBC-788W3-H689G-6P6GT Copy the oem-cert.XRM-MS to C:\Windows\system32\OEM (you might have to create the OEM directory).

Install cert license. cscript "%Windir%\System32\slmgr.vbs" -ilc "%Windir%\system32\OEM\oem-cert.XRM-MS" /f

If you need the certificate license, see: http://www.squidworks.net/wp-content/uploads/2015/03/SLIC.zip