Invalid Partition Table: Invalid partition table information.

Invalid Partition Table: Invalid partition table information.
Missing Operating System: “55AA” mark in DOS boot sector lost or DBR corrupted.
Disk Boot Failure: System file read failure.
Bad or missing command interpreter: Can not find command.com file or ‘COMMAND.COM’ file
corrupted.
Invalid system disk: DOS boot record corrupted.
Type the name of the command, Interpreter: DOS partition mark in partition table error or
‘COMMAND.COM’ file lost, corrupted.
Error Loading Operating System: Main boot startup program read boot sector unsuccessfully.
Not found any active partition in HDD: Active partition mark in partition table changed as inactive
partition mark.
2.Hardware reason
Sometimes data loss is because of hardware, such as bad sector in hard disk, power cut, head
damage, circuit panel problem, etc.
When your hardware has some problems, you probably will find: the speed of hardware become
slow, you cannot operate successfully; you cannot read data, etc, which are most often physical
bad track failures.
Correspondingly, data recovery in hardware fix is considered as hard recovery, such as memory
medium damage, track damage, hard disk scrape, head damage, electric machinery damage, chip
burnout and so on..
The most distinct feature or difference between soft recovery and hard recovery is whether the
memory medium itself can be normally accessed by fixing or replacing parts.