User's Guide for DOS

User Guide for Active@ UNERASER DOS:

3.4. Backing Up MBR, Partition Table and Boot Sector

This section contains an extremely brief description of some of the elements involved in low-level disk structures. Descriptions here do not cover all common scenarios. Descriptions are provided at a general knowledge level only.

It is important to make MBR and Partition Table backups regularly. If a partition becomes damaged and cannot be read by the system, restoring the MBR may be able to help resolve the situation.

The Master Boot Record (MBR) is usually located on the first physical sector of a hard disk partition. This is also called the Boot Sector. It consists of two parts:

• Executable code
• The Partition Table

When the PC begins the boot process, the executable code is run to determine which partition contains the operating system. Once determined, it instructs the operating system to take control of all systems.

Some hard drives use proprietary drive overlay software (e.g. OnTrack Disk Manager), to handle large drive sizes. When contemplating rewriting or by-passing the MBR, it is advisable to make a backup copy to simplify recovery.

To make backups of MBR, Partition Table or Boot Sector use the following steps:

1. Run Active@ UNERASER for DOS
2. Select the HDD which is to be backed up. Make a note of the name of the HDD
3. With the Active@ UNERASER floppy disk in drive A:, press [Ctrl]+[B]
4. Information will be saved to drive A: in a folder with the same name as the selected drive

For example, if HDD 80h is being backed up, the path to the saving location will be A:\HDD80h.MBR.

Using this floppy, the system's MBR can be virtually restored and partitions and drives will be viewable for the files and folders to be recovered.