With Windows Vista its possible you can get stuck sometimes with an error, which would look unrecoverable. Have you ever encountered the “BOOTMGR is missing”, I hope this error seems familiar.
Sometimes this error happens for unknown reasons, sometimes hardware issues!

Now to fix this quickly, lets boot off with the Windows Vista DVD now click Next at the first prompt:

When you move on to the next prompt, you should be able to see a link in the lower left-hand side “Repair your computer”

The process will automatically attempt to find your Vista installation directory. Select the one like its show below and then use the Next button again.

Now click on the first link for “Startup Repair”

Now the installation process will try to repair the system, and then prompt for you to reboot.

Just for the info you could use Command Prompt option instead, and use the following command to fix the boot options only:
bootrec /fixboot

Now restart your PC and you would get Vista up and running.
Add to

February 11th, 2008 at 2:59 pm
Nice tips. The error does not happen oftenly in my PC. Just sometimes, but it does really bothering. Anyway, after I fix up my PC using above steps, are you sure that this kind of error will not happen again? If it is caused by the hardware, are above steps will help?
February 11th, 2008 at 6:12 pm
This error normally comes because of errors in either the boot sector or of other problems with windows. Normally doesn’t occurs due to hardware errors.