Unclear what exactly you are trying to do - a vmdk file is a virtual hard disk (or a piece of one). You can't "install" it directly.
What host OS? What version of Workstation?
> Start tag expected, '<' not found KDMV
That is a message I have never seen before but it suggests that the file you specified is not in the propper format.
KDMV is the hex signature of a monolithic sparse VMDK and that signature is also used for the slices of a split sparse VMDK.