There is a way to move a virtual machine from Hyper-V to XenServer without the need for XenConvert. On Hyper-V do the following:
Power off the VM Backup or migrate to a CIFS share The backup or CIFS share will include the VHD files for the hard disks (one VHD per virtual hard disk)
On XenServer do the following:
Create a new VM with the correct configuration (CPUs, RAM, NICs etc) and correct number of Hard Drives. Modify the name of the virtual disks: storage tab, select disk, properties, change name to be something unique (for example TEST or VM-C-Drive or VM-D-Drive). Do this for each disk. Use the cli determine the SR uuid and vm disks uuid
xe sr-list (note the uuid of the correct storage repository)
xe vdi-list name-label=VM-C-Drive (or however named above) – (Note the UUID of each disk)
Copy the VHD files to the XenServer storage volume
Using WinSCP or similar copy to the following location (using the sr uuid determined above) /var/run/sr-mount/{SR-UUID}/
Rename
The VHD files have the filename of the uuid of the virual disk as determined above. Rename 0r delete the first hard disk assigned to this VM (the filename with the uuid of the VM-C-Drive disk) Rename the Hyper-V disk 1 to the same filename {Disk1-uuid}.vhd Repeat the process for each disk
Now you can power on the VM and it will boot from the hard disks copied from Hyper-V.
This seems like a lot of steps but it is pretty quick to do and means that XenConvert is not required (as was not possible in my case). The VM will configure the new devices during the first boot, reboot and then be ready to use.