How to Manually Repair Windows 7 Boot Loader Problems

출처: How to Manually Repair Windows 7 Boot Loader Problems

Repairing the Master Boot Record

If you want to restore the master boot record, you can simply type in the following command:

bootrec /fixmbr

You can also write a new boot sector onto the system partition with this command (which is often more useful):

bootrec /fixboot

And of course, if you just use bootrec /? you’ll be able to see all the options.

 

Replacing the Windows XP Bootloader with Windows 7

If you’ve managed to install XP on the same PC that you already had Windows 7 on, you’ll noticed that you can’t boot into Windows 7 anymore. You can use this command to fix that and restore the Windows 7 bootloader:

bootsect /nt60 all

Depending on the partition that you’ve installed, you might need to substitute the drive letter instead of “all”.

 

Note: if you want to restore Windows XP back to the menu, you can open up a command prompt in Windows 7 and run this command:

bcdedit /create {ntldr} -d “Windows XP”