I just read the following in the VBox User's Manual.
"Warning: Setting up Host Interface Networking requires changes to your
host's network configuration, which will cause the host to lose its network
connection. Do not change network settings on remote or production systems
unless you know what you are doing."
Sounds exactly like what I'm experiencing. Apparently I am still doing
something wrong in my networking to cause this. Obviously I don't know what I
am doing. Could it be Logical Adapter numbers or wrong protocols? What else
could it be?