and answered many times in the Storage Forum.
Please take a moment to read what has already been covered ad nauseam in the Storage Forum.
If after reading the many posts you still have questions ....then ask the followup question(s).
Re no backup or other copy of the needed data....why ??
I have an HP simple save 500GB hard disk that has suddenly stopped being read. I can hear the motor, so it's not a power problem, I think. All of my stuff is in there and I really need it! On trying to open it, it says parameter is incorrect. So I ran a chkdsk via CMD, but that got stuck at 73% on step 2 twice, and now it is asking me to format disk. I cannot do that!I do not have back up!!