virtualbox.org

I have tried this with 5.2.44 32 bit on windows and 6.1.16 64 bit on windows

I have tried using copy from within the media manager and also from the command line
In all cases it ran for a couple of minutes or more and failed in the final seconds with a VBOX_E_FILE_ERROR 0x80bb0004 in MediumWrap

I wondered if it was the dynamic VDI file so I converted this using the command line to a fixed size VDI which worked fine
I tried converting this to a VHD with the same error at the same point in the cycle

I tried using media manager copy and from VDI to VMDK and this worked fine as well
I tried converting this to a VHD with the same error at the same point in the cycle

I tried the same VDI to VHD conversion under Ubuntu and that didn't work either

So I have come to the conclusion that VboxManage cannot produce VHD files, unless you know better

Don't know: sane people generally avoid VHD anyway - it comes right out of the box as a disaster waiting to happen. The design is straight up stupid and error prone. Nobody uses it anymore, not even Microsoft (they switched to VHDX, which despite the name similarity is a completely redesigned format).