Restoring the MBR for Windows 7

During my explorations of dual-booting of Windows 7 and Ubuntu 10.10, I ended up restoring the master boot record (MBR) so that Windows 7 could load again or to find out if it wouldn’t start for me. The first hint that came to me when I went searching was the bootsect command but this only updates the master boot code on the partition so it did nothing for me. What got things going again was the bootrec command.

To use either of these, I needed to boot from a Windows 7 installation DVD. With my Toshiba Equium laptop, I needed to hold down the F12 key until I was presented with a menu that allowed me to choose from what drive I wanted to boot the machine, the DVD drive in this case. Then, the disk started and gave me a screen where I selected my location and moved to the next one where I selected the Repair option. After that, I got a screen where my Windows 7 installation was located. Once that was selected, I moved on to another screen from I started a command line session. Then, I could issue the commands that I needed.

bootsect /nt60 C:

This would repair the boot sector on the C: drive in a way that is compatible with BOOTMGR. This wasn’t enough for me but was something worth trying anyway in case there was some corruption.

bootrec /fixmbr
bootrec /fixboot

The first of these restores the MBR and the second sorts out the boot sector on the system drive (where the Windows directory resides on your system. In the event, I ran both of these and Windows restarted again, proving that it had come through disk partition changes without a glitch, though CHKDISK did run in the process but that’s understandable. There’s another option for those wanting to get back a boot menu and here it is:

bootrec /rebuildbcd

Though I didn’t need to do so, I ran that too but later used EasyBCD to remove the boot menu from the start-up process because it was surplus to my requirements. That’s a graphical tool that has gained something of a reputation since Microsoft dispensed with the boot.ini file that came with Windows XP for later versions of the operating system.