The loader for a convenient wubi-installation of Ubuntu, can be easily re-added to the Windows Vista/Windows 7 bootloader.
After you have transferred all Ubuntu related files to the new root drive (files: wubildr and wubildr.mbr and the ubuntu directory), open a new Console as Administrator and run the following commands to add Ubuntu to the boot menu:
bcdedit /create /d "Ubuntu" /application bootsector
This will return an identifier in the form of a GUID – in the following commands, replace{ID}by that identifier!bcdedit /set {ID} device partition=C:bcdedit /set {ID} path \wubildr.mbrbcdedit /displayorder {ID} /addlast
Done. Upon the next boot, a new entry Ubuntu should appear in your boot menu.