Hi, I realised the problem could come from the graphical interface loaded by Gnome, since Debian was able to start in recovery mode. For a strange reason I could not configure my ethernet connection properly in that mode and had therefore not the possibility to download install drivers using apt (sideloading it was working but the drivers I needed where too complicated to get that way).
In order to install all the firmware for my graphic card (nvidia GTX 1650) I entered the rescue mode and followed all the steps of the setup leading to the selection of the partition of the root file system to repair. Taking advantage of the hardware detection and settings run by the installer to have a working ethernet connection, I launched a shell in the target debian root file system and I was then able to set `apt` to get the firmware needed and install them. I was then able to reboot into Debian with the full Gnome desktop environment. Regarding Grub that noticed the Windows partition at installation, but did not write it on the boot table, a simple `update-grub` from the recovery mode fixed it, and I did not have to configure the menu.lst file as suggested in the FaQ (https://wiki.debian.org/DebianInstaller/FAQ#Q:_What_do_I_do_if_I_can_no_longer_boot_Windows_after_installing_Debian.3F <https://wiki.debian.org/DebianInstaller/FAQ#Q:_What_do_I_do_if_I_can_no_longer_boot_Windows_after_installing_Debian.3F> ). This therefore raises two questions from my part: 1/ Is Grub not updated after writing the new boot loader to the MBR? 2/ Would it be possible at the final step of the installation, just before the reboot, to allow the use of a shell running in the newly created debian file system in order to install additional firmware that could not be loaded in another way and that are needed for some DE for example? (In my questions I am referring to the graphical installer in standard mode, as I don’t feel confident enough to use the expert mode, and thus don’t know if this is already accessible in that mode). Apart from this, many thanks it worked great! Ambroise
