Milestone 5
Setting up mail service on the server was trivial: just a matter of clicking a few buttons in VHCS. So, I have no idea what the problem was on the Win/ux box that prevented proper mail service, and, frankly, I don’t much care.
As for the CPU idle time, well now that all the server processes are installed and running, it’s sitting around 99% on average. Which is nice. load average: 0.00, 0.00, 0.00 is pretty much what I want to see from an idle server.
Final Result: Mail service is being handled by the server again. The OS transition is complete.

check this website for good installation steps http://www.debianhelp.co.uk/vhcs.htm