Which target format (thin, or thick) do you want/need?
In case you want to clone the virtual disk as is, omit "-d thin" from the command line.
I would rather stick with the original format. It looks that I have added thin just because it was in the step by step guide. I will therefore omit "-d thin" as mentioned above.
There are a couple of ways to find out whether a virtual disk has been thin, or thick provisioned. An easy way is to run ls -lisa, and compare the provisioned size (the column left to the time stamp) with the real size in kB (2nd column). If the sizes match, the virtual disk has most likely been thick provisioned.
Here is the output of ls -lisa (original VM folder):
It looks that the size does not match and it therefore was most likely using the thin format of provisioning.
I'm not 100% sure about this, but I'd give it a second chance. Maybe it's a result of converting a thick disk to a thin disk!?
I will give it one more chance and if that will not work I will most likely try that VM Explorer with a hope that it will allow me to move from one datastore to another without getting my local Windows computer involved in terms of its hard drive.