How to repair the Boot Manager
Rewrite Masterbootrecord:
bootrec /fixmbr
Scan for all OS:
bootrec /scanos
Adds found OS into Boot Manager:
bootrec /rebuildbcd
Recreate Boot Manager:
bootrec /fixboot
Important: The partition with the boot manager needs to be active to be able to boot Windows 2008 R2 or Windows 2012. If it is not active you can make it active with diskpart:
1. Run DVD Repair Mode
2. diskpart
3. select disk 0 (For the first disk)
4. select partition 1
5. active
6. exit
7. Restart Computer
admin on January 18th 2013 in IT, Windows, Windows Server