Can't launch guest

[nwm]

I just updated to 4.3.16. I have a windows host and slackware Linux guest. When I try to launch my guest I get these errors:

I was previously running 4.3.12 where it worked fine.

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Failed to create the VirtualBox COM object.

The application will now terminate.



Callee RC: E_INVALIDARG (0x80070057)

Failed to open a session for the virtual machine slk.

The virtual machine 'slk' has terminated unexpectedly during startup with exit code 1 (0x1). More details may be available in '..\VBoxStartup.log'.

Result Code: E_FAIL (0x80004005)
Component: Machine
Interface: IMachine {480cf695-2d8d-4256-9c7c-cce4184fa048}

[nwm]

ok... I guess I'll just reinstall v12 and wait till the next release version comes out..