Well after wasting a lot of time and utilizing lot of efforts. You need to download 6.0 image and flash it with that image. After installing 6.0 you may upgrade online.
Thank you for this solution! I was going crazy because, after the flashing of OpenPli 8.3, I was unable to return to one of the others images I had on my multiboot. I tried all of my usb memory stick (that I used positvely a lot of times before), but I obtained just a lot of fails.
So I found your post and I tried and all is ok now, my H7S is back to his prevous state now.
