Read this article: http://www.outlookcode.com/d/cdo.htm
as it will explain CDO a little bit more. Also note from the copy that CDO is NOT offically supported in the framework although it can be done.
Also, I know that it is possible to connect to an exchange server via Sockets (TCP) and passing a username and password to the server.
Much like anything in programming, there is definately more then one way to achieve your desired end result, how you get there is up to you.
Read this if you want to know how to get a correct reply for your question:
^^Took that from planoie's profile^^
^^Modified text taken from gbianchi profile^^
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