Write new Windows 7 or Windows Server 2008 R2 bootloader:
BOOTSECT /NT60 C: /FORCE /MBR
Create a BCD store from Windows VHD:
DISKPARTSELECT VDISK FILE=C:\BOOTVHDS\W2K8R2ENTX64.VHDATTACH VDISKASSIGN LETTER=XEXITBCDBOOT X:\WINDOWS /S C:
Set up VHD native boot:
BCDEDIT /SET {default} DEVICE VHD=[LOCATE]\BOOTVHDS\W2K8R2ENTX64.VHDBCDEDIT /SET {default} OSDEVICE VHD=[LOCATE]\BOOTVHDS\W2K8R2ENTX64.VHDBCDEDIT /SET {default} DETECTHAL ON
Set up legacy boot:
BCDEDIT /CREATE {ntldr} /d "Chain Legacy Bootloader"BCDEDIT /SET {ntldr} DEVICE PARTITION=C:BCDEDIT /SET {ntldr} PATH \ntldrBCDEDIT /DISPLAYORDER {ntldr} -ADDLAST
To put things back to normal, should you ever need to:
BOOTSECT /NT52 C: /FORCE /MBR
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