Data loss: System problem

The main symptom is that you cannot enter the system or the system is abnormal or computer closes down.

The following are prompts that system can not start up normally:

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.