VirtualBox upgrade trashed my virtual machine [closed]

Question

I had Virtual Box 3.2 working fine, emulating 32-bit Windows XP in a 64-bit Windows 7 host. Then I upgraded to VirtualBox 4.0.4, and everything seemed to work (after I installed a couple of things -- USB2.0 support, Guest Additions).
Then I restored a snapshot that was taken under version 3.2, and now I've lost everything. I get the error message:

The selected virtual machine is *inaccessible*. Please inspect the error message shown
below and press the **Refresh** button if you want to repeat the accessibility check:

Could not find an open hard disk with UUID {b0e666ef-1041-415a-8329-876b337e1958}.
Result Code: 
VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)
Component: 
VirtualBox
Interface: 
IVirtualBox {d2de270c-1d4b-4c9e-843f-bbb9b47269ff}

I tried creating a new virtual machine from the vdi file, but it locks up when loading WINDOWS\System32\DRIVERS\lfsfilt.sys. I tried re-installing version 3.2, but I get exactly the same problems.

I have a VirtualBox.xml file in my .VirtualBox directory, and various files (Virtual Dell.xml, Virtual Dell.xml-prev etc.) in .VirtualBox\Machines\Virtual Dell.

Help please! How do I get my virtual machine back?

Answer 1

This bug happened to me recently (I assume it's a VirtualBox bug) using snapshots in v4.

I fix'em opening the VirtualBox.xml file and:

1. Search the UUID of the missing drive (b0e666ef-1041-415a-8329-876b337e1958 in this case), normally will be a tag (notice the />).
2. Remove the tag which generate the error.
3. Now, if the problematic HardDisk tag was inside another HardDisk tag (one with open and close tag) reconvert this last tag in one without close.

Sorry, my english it's not good enough for a good explanation, let me show you an example:

Original non-working XML piece:

<HardDisks>
    <HardDisk uuid="{ac511969-288a-44b4-b7ac-df5808c1a4ca}" 
        location="/home/me/.VirtualBox/HardDisks/machine_name.vdi" 
        format="VDI" type="Normal">
        <HardDisk uuid="{e4e44e9d-aad0-4e2f-8ef8-d3d4d64f997f}" 
            location="/home/me/.VirtualBox/Machines/machine_name/Snapshots/{e4e44e9d-aad0-4e2f-8ef8-d3d4d64f997f}.vdi" 
            format="VDI"/>  <!-- Problematic snapshot -->
    </HardDisk>
</HardDisks>

Fixed XML piece:

<HardDisks>
    <HardDisk uuid="{ac511969-288a-44b4-b7ac-df5808c1a4ca}" 
        location="/home/me/.VirtualBox/HardDisks/machine_name.vdi" 
        format="VDI" type="Normal" /> <!-- Notice we've changed this tag and remove his closing tag since it's not more needed -->
</HardDisks>

This at least works for me, I loose the snapshot but recover the virtual machine.

Hope this help you.

Answer 2

in Virtual Media Manager, is the XP VDI disk attached to the virtual machine? If it is not then open settings for the VM and add the VDI in the Storage tab