This is like more a cookbook which was searched because of a need: after some trouble with hardwares, the old Windows Server virtualized in Virtualbox box didn’t run – and for that reason was documented here to use in the future.
Since most of my things are now beeing virtualized, and in my day Job i already use Hyper-V to use my virtual os’es didn’t find a reason to do this in other pcs.
So it’s pretty easy to convert the image. Just open the Virtualbox folder, open a command prompt there and throw some commands like this:
vboxmanager.exe internalcommands converthd -srcfromat vdi “C:\original\old.vdi” -dstformat vhd “C:\newVHD\new.VHD”
It will take some time, but after that you just have to create a new Virtual Machine in Hyper-V, configure it, and boot it up.
Works like a charm.