Voici la réponse que j'ai trouvé à ma question ds un forum américain spécialisé en MSI:
when you have load ""load fail-safe defaults" parameters its disable USB controller for diagnostic mode and normal your keyboard or mouse which is USB guess to stop working.
power down your machine, remove power cord from the PSU, hit few time power button to drain electric from capacitors, touch some metal with hands to discharge any ES which may you have, open the case and look for jumper JBAT1:
move jumper to Clear Data position, wait 1 minute, then move jumper to the Keep Data position.
pull back power cord to the PSU, and turn your PC, go into BIOS and select "LOAD BIOS DEFAULT" (NOT "failed safe parameters), then SAVE AND EXIT.