I hope my hard disk is ok... I'll wait and if I get another SMART warning I'll back up all my data, anyway I have 2 hard disk drives and I have backed up some important files.
I have tested my hard disk with Active SMART, it says everything's OK, it has everything in green but an unknown attribute (ID CA) is in red

. That soft says "1 SMART attribute changed. SMART reported good status" so I don't understand what the red attribute means...