voila la solution :
To resolve this behavior, follow these steps:
Start Internet Explorer.
In the Address box, type https://v4.windowsupdate.microsoft.com/getmanifest.asp, and then click Go.
In the Revocation information about the certificate was not available... do you still want to connect? dialog box, click Yes.
On the Tools menu, click Windows Update.
On the Windows Update Web page, click Scan for Updates
C'est un probleme de certificat...