My Ubuntu is not starting anymore, end on on BusyBox / initramfs
A friend of mine https://twitter.com/CyrilBrulebois solved it for me. Here is what he advised me to: 1) use a live ubuntu usb key 2) once ubuntu loaded just go to the terminal, then enter dmesg command. 3) he reads the lines and one was saying that one device has been found and the mode was changed from AHCI to RAID and here was the thing. 4) I went on the BIOS and changed the Sata configuration to Raid to AHCI then everything goes back to normal. I was ready to purchase a new hard disk, now I am happier than ever. Thank you so much for your help