WIN8 system boot appears missing operating systems how to do?

WIN8 system boot appears missing operating systems how to do?

Reason Analysis:

1, the system leads the area to appear the problem;

2, the computer was attacked by the virus;

3, the hard disk problems.

Typically, there is an error in the system boot record. The system boot record is located in the logical 0 sector and is generated by the Advanced Formatting command format. After checking the partition table correctly, the main boot program reads the system boot record according to the starting address of the system partition indicated in the partition table, and if read fails, displays the error loading operating system, and if you can read the boot record correctly, The primary bootstrapper checks to see if the last two bytes of the system boot record are 55AA, and if not the two bytes, give the "Missing operation system" hint.

Workaround:

1, partition disk to repartition, is estimated to be 0 track error, so the partition is first extended partition or hidden partition (must have), the main partition in the final, because 0 track can do guide, 255 track can also do guidance.

2, the system must start three files: Msdos.sys,io.sys and Command.com, you can use the system reply disk into a DOS program copy into the system disk:

Type copy MSDOS. SYS C:

Type copy IO. SYS C:

Type copy Command.com C

In general, it can be repaired with NDD. If unsuccessful, the DOS boot record is rewritten with the format c:/s command. If the problem persists, it can be solved by reloading the system.