You can use a disk utility to edit bytes in the MBR directly from the disk or
You can use BCDedit in Vista and Windows 7 see links
When MBR fails then the operating system will not load.
Full form of MBR is Master Boot Record in computer hardware field...
MBR (Master Boot Record) - this is because prior to windows vista all x86 based computers used the MBR partition style only.
I our company's case I understood it to mean "member". I was the contact person for our Limited Loss Company, and MBR was inserted after my name in the official EIN document. Furthermore, an IRS document found in the internet has this: "A single member or sole member LLC account will contain the words "SOLE MBR" or "SINGLE MBR" within the Sort Name line as shown on CC INOLES" So: MBR = member.
on Sector 0
Mbr<-pc mar<-x pc<-y memory<-mbr
The Master Boot Record (MBR) is stored at the beginning of your hard drive (in the first 512 bytes.) The MBR contains information about the beginning and ending of each partition, which partition contains the operating system for booting, and other valuable information about the disk layout. Your computer will not boot up if your MBR is corrupt or missing.
MBR Master Boot RecordA Master Boot Record (MBR), or partition sector, is the 512-byte boot sector that is the first sector ("Sector 0") of a partitioned data storage device such as a hard disk. ( from: http://whitehouse.com)
BIOS reads the MBR.
A Master Boot Record (MBR) virus specifically targets the boot sector of a hard drive, where the MBR is located. This type of malware can overwrite the MBR, rendering the system unbootable and potentially corrupting the data on the drive. MBR viruses often propagate through infected floppy disks or USB drives, and they can be particularly difficult to remove without specialized tools. Users should regularly back up their data and use antivirus software to protect against such threats.
2 TB
The easiest method under Windows is using an application such as MBRWizard (link provided below), which can delete, create, or even repair a corrupt MBR.