How to Fix the "Bootmgr is missing" Error in Windows

Boot your computer to the Windows 7 DVD (or to a "Repair CD"). At this screen choose to install now.

2. Select your language and click next.

3. Click the button for "Use recovery tools".

4. Then select "Command Prompt".

5. When open, the command prompt will look like this:

6. The command we will use, bootsect.exe, is in a folder (named boot) on the DVD.

We need to know what drive letter has been assigned the DVD drive to access the folder.

Code:

Type: diskpart
and press Enter
 
Type: select disk 0 (zero)
and press Enter
 
type: list volume
and press Enter

In this screen shot, the 7 DVD is letter: G

7. Use your DVD drive letter and

Code:

Type: exit
and press Enter
 
to close Diskpart
 
Type: G: (use the letter of your DVD drive)
and press Enter
 
Type: cd boot
and press Enter
 
Type: dir
and press Enter

to verify that bootcect.exe is there (if you really need to)

8. To restore the "bootsector code":

Code:

TYPE: bootsect /nt60 SYS /mbr
and press Enter

NOTE: If this method fails to restore the MBR, you can try the bootrec command as it is also a tool for repairing the MBR.

9. When completed successfully,

Code:

Type: exit
and press Enter

This will close the command prompt window.

10. Now select Shut Down or Restart

11. Then you can reboot your computer into Windows.
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