Le 03/09/2017 à 19:40, Thomas Schmitt a écrit
I will explain (what I remember) what I did tomorrow.Don't forget it.
I formated the USB as FAT32 in my iMac I downloaded the firmware version firmware-9.1.0-amd64-netinst.iso Then I did sudo cp firmware-9.1.0-amd64-netinst.iso /dev/disk1 When this command finished I had a system message: "The disk you inserted was not readable by this computer." and I did diskutil unmountDisk /dev/disk1 Then all went well. But not the resolution. So after a little Googling I found this https://gist.github.com/ed-flanagan/929633981ea548e97f1d and now it's working like a charm. And thanks again to all of you Luis