This article was previously published under Q166997
The master boot record is required to boot your computer. Having a currentbackup of your master boot record is an excellent way to ensure that, inthe event of a virus or hardware failure, you will be able to recover yoursystem in the shortest amount of time possible.
After the Power on Self Test (POST) is complete, the system BIOS loads thefirst sector of the hard disk drive into memory and transfers execution tothe code that was at that location. That code reads the partition table tolocate the system partition and, after finding it, reads in the firstsector within that partition (the boot sector) and transfers execution toit. That code contains the information necessary to start the operatingsystem.
If for any reason, a link in the boot sequence is broken, the system willfail to start. A backup copy of the boot sector is already stored on thehard disk but a backup copy of the master boot record is not.
If you have saved a copy of your master boot record, you will be able toreplace this critical sector of your hard disk drive and get the systemback in operation quickly.
By following the solution listed below you will be able to successfullyback up your master boot record to a floppy disk. With that file and NortonDisk Edit, you will be able to restore your back up copy to the harddisk in the event of corruption because of a virus or malfunctioninghard disk hardware.
Obtain a copy of Norton Disk Edit.
Copy the following files onto a DOS 6.22 bootable disk:
DISKEDIT.EXE NLIB200.RTL YMCFG.BIN
A mouse driver is also very handy but not necessary.
Create an Autoexec.bat file that starts Diskedit with the /W switch to make it possible to write your changes to the hard disk drive.
Start Disk Edit and from the Object menu, click Drive.
From the displayed dialog box, click Physical Disk.
Select Hard Disk One and click OK. You are now looking at the master boot record and partition table.
From the Object menu, click Partition Table.
From the Tools menu, click Write Object To. To a File is already selected so click OK.
Type a path back to drive A and select a filename to use. For example,
Click Yes when prompted.
Click Cancel at the Rescan prompt.
This completes saving a copy of your master boot record on to the floppydisk that you used to boot to DOS and run Disk Edit.
To Restore the File In the Event of Corruption
Using the same disk as before:
Start Disk Edit and from the Object menu, click File.
From the Files dialog box, double-click you saved master boot record.
From the Tools menu, click Write Object To.
Click Physical Sectors.
Click Hard Disk 1.
Set the Cylinder to 0, the Side to 0, and the Sector to 1.
Click OK again on the pop-up Warning! message box.
This completes restoring your master boot record to the hard disk drive.