virtualbox.org

My host computer is Mac mini with OS X 10.8.2 mountain lion.
I downloaded and installed Virtual Box 4.2.12 r84980.
I tried using older versions of Virtual Box. It did not solve the problem.

When I try to start the VM it says:

Failed to open a session for the virtual machine CS50 Appliance 2.3
Nonexistent host networking interface,name "
(VERR_INTERNAL_ERROR).

Details
Result Code: NS_ERROR_FAILURE (0x80004005)
Component: Console
Interface: IConsole {a whole bunch of numbers}

I'm not certain about this configuration error, it's one of two things.

(1) I think it's the bridged networking error, i.e. you are trying to bridge to a host network card that doesn't exist. Perhaps you moved hosts? Perhaps you sometimes bridge to a USB wireless dongle?

(2) Less likely, you are using host only networking, and are trying to connect to a custom named host-only network which is no longer defined in the global VirtualBox preferences.

A glance at VM settings | Storage ought to tell you what it is.