Nicolas de Wilde stuurde mij een mailtje met de volgende tip:
Occasionally ESX VMs crash in such a way that the descriptor file of a vmdk gets lost.
If you ever need to recreate a descriptor from scratch but still have the *-flat.vmdk this little tool may come handy.
Tool asks for a flat-file – like used by ESX 3 and Workstation. It ignores the CID and uses a bogus one. Output is named "newdescriptor.vmdk" – rename as needed. Doesn’t work for disks smaller than 1 Gb at the moment.