Virtualbox headless: How to join and convert segmented vmware images into vbox

I found the problem.

It's because the disk where the VM image resides in is corrupted. If I go to

start->control panel-.Administrative tools->even viewer->system

I will find this message:

The device, \Device\Harddisk1\D, has a bad block.

This indicates that there are bad sectors.

In this case, the only solution seems to be changing the hard disk all together.

Here's an updated answer as of version 5.0.14, shown below:

From the main window, click the File menu and select "Virtual Media Manager" or simply use the shortcut Ctrl+D.

Select the disk you want to convert and click "Copy" or use the shortcut Ctrl-O.

Choose a path and filename for the converted disk, along with the file type, and click "Copy."

Note: The source hard disk will already be selected if you chose it in the previous step.

In my case, I converted a VDI of Windows Server 2016 TP4 into a VMKD for hosting in a corporate VMware environment. Both source and destination files were Dynamically Allocated.