BOOTMGR IS MISSING
Press Ctrl +Alt +Del to restart
This is what happened to one of my friends today, after inserting a brand new 400GB hard disk to two years old Compaq Presario system.Usually, this boot time error occurs when you insert a new hard drive or when you change the current hard drive settings like master to slave or slave to master. If you don't know how to fix this error, obviously you reinstall Windows Vista. But, you can fix this problem easily as follows:
♦Insert your Windows Vista DVD into your optical drive(DVD drive) and restart the system.
♦Boot using this DVD by pressing any key when windows asks "Press any key to continue..".
♦Select your language in the first screen and click "Next".
♦In this Window, select the option named "Repair your computer".
♦This tool will search for the installation directory for a minute.Once it finished, click "Next" once again.
♦Under Recovery Tool, choose the option named "Startup repair". Now,Windows will try to repair your startup problem and gives a message to restart your system.

♦Restart your system to finish the process.
Note: You can also choose command prompt instead of "Startup repair".Type in "bootrec /fixboot"(without quotes) to fix the above problem.
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