29c06976___lost_external_hard_disk_data__Reason_for_Data_Loss
[Scenarios] Loss of file due to BAD sectors [Reason for Data Loss] 
Because of the scratches on Disk platter, bad sectors are formed in your external hard drive, due to which your files become in accessible. You may lose your file, if you try to recover files from these bad sectors.
External Hard Drive File Recovery - Tool to restore deleted / lost external hard disk data
Reason for Data Loss