Transferring machines between computers fail.

[PlaceHolder]

Two machines, Linux Mint 18 and Linux Mint 19.

Linux Mint 18 is running VB 5.xxx and the Linux Mint 19 is running 6.xxxx

We are trying to transfer the entire machine folder (logs/snapshots/vbox/Disk1.vmdk/etc) from Machine 1 (Linux Mint 18) over to Machine 2 (Linux Mint 19).

When we transfer the entire machine folder, and try to open it, we get:

Medium '/xxx/xxxx/Documents/xxxx/Windows2K16_Disk1.vmdk' cannot be closed because it is still attached to 1 virtual machines.

Result Code: VBOX_E_OBJECT_IN_USE (0x80BB000C)
Component: MediumWrap
Interface: IMedium {ad47ad09-787b-44ab-b343-a082a3f2dfb1}
Callee: IVirtualBox {d0a0163f-e254-4e5b-a1f2-011cf991c38d}
Callee RC: VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)

No idea how to fix this... One thing we were able to do is create a NEW machine, and then use the same hard_drive.vmdk.... But we lose all the snapshots, which is *alright* I guess but why is this happening? Any suggestions?

We have tried closing VM and then reopening and trying to reimport... We have restarted the computer already, etc etc.

EDIT: SEMI SOLUTION
Went and edited VBOX file and got rid of something like (but not exactly):

<StorageControllers>
  <StorageController name="SCSI" type="LsiLogic" PortCount="16" useHostIOCache="false" Bootable="true">
    <AttachedDevice type="HardDisk" port="0" device="0">
    <Image uuid="{bc1814cc-033f-4c5d-bfbd-1ffc7c739527}"/>
    </AttachedDevice>
  </StorageController>
</StorageControllers>

near the bottom of the file on what I THINK was the latest snapshot.... Then I re-added it and had to change a bunch of settings, then it failed, then I did it again, failed, then I did the same exact thing again and it worked.

Wow.

[socratis]

Here's the deal... If you want help, you got to be 1) accurate, 2) not hiding, 3) not "thinking" but "knowing". Which translates to:

• No "running VB 5.xxx" and "running 6.xxxx", there are exact versions, please get the facts straight. Going to the doctor with a "I'm having a pain in the vicinity of my torso" is not going to be helpful for an accurate diagnosis...
• No "Medium '/xxx/xxxx/", because my answer is going to be full of the same "x" letter as well. If you want us to do a diagnosis, you can't be xxx-ing anything. No one got ever hacked by their username alone. Security is a GoodThing™, paranoia is a BadIdea™.
• No "got rid of something like (but not exactly)". What do you want us to do? Start throwing the dice to see what we might come up with? Guessing? All of the above?

then I did the same exact thing again and it worked

Does that mean that your problem is actually solved?

For future readers, see the FAQ "Moving a VM" for the proper way to move a VM...