Hack 48 Fix the Master Boot Record on NTFS Partitions

Windows NT, 2000, XP, and Windows Server 2003 users having problems accessing or booting from an NTFS disk can use the FIXMBR program to rewrite a new Master Boot Record on the hard drive.

FIXMBR is available only through the Recovery Console feature of Windows NT, 2000, XP, or Windows Server 2003. To access the Recovery Console, you must boot up with recovery diskettes you made during installation of the OS or select the recovery options from the installation CD. FIXMBR has one function, just like DOS's FDISK /MBR: to write a new Master Boot Record on the disk drive.

Do not use the DOS FDISK program to replace the Master Boot Record on an NTFS drive, as doing so can render the drive and data inaccessible.

Boot using your Recovery diskettes or setup CD and select the Recovery Console option.
Log on to the drive/partition you wish to repair, typically C:\WINNT or C:\WINDOWS.
At the command prompt, issue the MAP command to determine the device name for the disk partition you want to "fix"�typically it will be \Device\HardDisk0.
At the command prompt, issue the FIXMBR command followed by the name of the disk partition to be "fixed." For example (press Enter after the command):
```
fixmbr \Device\

HardDisk0
```
Type exit to leave the Recovery Console and restart the system.

Do not use this method to repair a primary active boot partition that uses GRUB or LILO boot managers [Hack #50] . Apply it only to the specific drive or partition containing an NTFS boot sector.

If you do not supply a device name, a new Master Boot Record will be written to the default boot device, which is typically what you want to do anyway.

If an invalid or nonstandard partition table signature is detected by FIXMBR, you will be asked if you want to continue with FIXMBR or not. How you proceed is determined by whether or not you are having problems accessing the drive. If you are not having problems accessing your drives, you should not continue.

Writing a new Master Boot Record to your system partition could damage your partition tables and cause your partitions to become inaccessible