This is a situation that every tech support person has faced or will face at least once:
a failed hard drive.
In this particular case, a user was getting errors like “disk 0 error” and “invalid drive specification.” Here were the other facts in the case:
• The data wasn’t backed up.
• The problem came out of nowhere.
• The user had accessed Setup and tried to manually enter the settings for the drive type when
“Auto” didn’t work.
• There was no startup disk made by this machine.
Reviving a drive like that one—even if only long enough to copy its data before you throw the drive in the garbage—is a tough challenge.