Here are few steps you can try to fix the missing bootmgr:
- Boot from Windows installation CD and select Repair then Command Line tools and type the following command line:
- If any of the first method did not help, then type this command lines:
bootrec /fixmbr bootrec /fixboot bootrec /rebuildbcd
- If none of this helps then try to run the Windows repair or restore a backup in case you have one.
- If any of above did not fix the problem then you may have to re-install Windows.
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