Had V4.3.14 of Virtual Box, and ran latest Windows update (Nov 13, 2014) and received the Hardening error.
So I updated to V4.3.18 of Virtual Box and this issue was resolved i.e. Virtual Machines now open and work correctly.
The issue I am now facing is that my Host computer can connect and access the Internet until I run a Virtual Machine. When I do this my Internet browsers (in the Host) can no longer access the Internet, yet the Virtual Machine can access and use the Internet without any issues.
When I run a Windows diagnosis on the Host as to why it cannot access the Internet it says: No Problem Found - yet all browsers say cannot connect or page cannot be found. If I restart the Host computer, all the browsers work again as per normal until I run a Virtual Machine and then they stop working again.
I have tried running: ipconfig /flushdns and netsh winsock reset but the problem still exists.
I am not certain as to what the conflict may be and would much appreciate any advice.
Thank you