Hi Didier, welcome to the Seven Forums.
It looks you have sysprepped your PC in Audit Mode
. When Audit Mode starts the sysprep window is always shown. Also, if you have not chosen to exit Audit Mode, PC will after reboot be back in Audit Mode and the sysprep window shown.
To exit Audit Mode and enter the normal setupmode (OOBE or Welcome mode), you need to select System Cleanup Action: Enter System Out-of-Box Experience (OOBE)
and Shutdown Options: Shutdown
(or reboot) and click OK: