I decided to upgrade VirtualBox because the newer versions have much better support for networks that allow virtual computer to be visible on the real network.
But after upgrade I encountered the error
"HostInterface’: The attribute ‘name’ is required but missing."
It seems others have had similar issues
I resolved this by deleting this entry:
from the config file, in my case this was
After this the virtual machine worked fine - and the new network settings are great.