16.04 - Fresh install of Ubuntu, Virtual box no longer works

Recently upgraded Ubuntu via a fresh install of 16.04 Lts 64bit, kept home folder contents into new installation, but now Virtual Box (5.0.40) has problems, when I try to start a machine from saved state (Ubuntu 14.04 32bit) - I get error message:

Failed to open a session for the virtual machine Ubuntu 14.04 32bit
Failed to load unit 'cpum' (VERR_SSM_FIELD_OUT_OF_BOUNDS).

Result Code:

NS_ERROR_FAILURE (0x80004005)

Component:

ConsoleWrap

Interface:

IConsole {872da645-4a9b-1727-bee2-5585105b9eed}

Does anyone know of a solution? Thanks

Assuming that you're running identical releases of VirtualBox, according to this thread on Virtualbox.org: https://forums.virtualbox.org/viewtopic.php?f=8&t=77554

You'll need to delete the saved state of your VM, as the change to the host OS is enough to cause the problem you describe with the VM.

That said, my own experience suggests that just moving between VirtualBox versions can cause problems with VM saved states. Again, the solution is to delete the saved state of the VM.

Rich