Hello Mark.

Well, I have OE insttalled. It's not my default email client. Is that important?

Well, I just tested and I was able to successfully send an e-mail using CDo for Windows 2000 on my machine which has OE installed and configured but which has Outlook XP set up as the default e-mail client.

As I have already said, the documentation in the MSDN library is very good. This is what the platform SDK: CDO for Windows 2000 (Configuration CoClass topic) has to say on the subject:

Remarks
Configuration settings are used by the Message object to specify certain operations, such as whether messages are sent using a Simple Mail Transfer Protocol (SMTP) service pickup directory, or sent through an SMTP service directly over the network. Configuration settings are made up of a set of fields (properties) that consist of name/value pairs. Each field is represented as a Microsoft® ActiveX® Data Object (ADO) Field object that is contained in an ADO Fields collection. To make them unique, most field names reside in the http://schemas.microsoft.com/cdo/configuration/ namespace. Additionally, the urn:schemas:calendar:timezoneid field is used within the Configuration object to set the local time zone.

To configure Message objects, you modify fields in the associated Configuration object. You can either modify fields in the existing Configuration object or create new Configuration object and set the Message object's Configuration property to this object.

In many cases, the default configuration settings are sufficient to send and post messages successfully. The default configuration settings depend on the software installed on the computer on which you are using the CDO component. When you send messages without associating a Configuration object, these defaults are used; for example, if the computer has the SMTP service installed, the default configuration for sending messages is to write them into files in the SMTP pickup directory. Additionally, various settings can be loaded from Microsoft® Outlook® Express if it is installed. For more information about default settings, see the configuration fields section of the reference.

Depending on the software installed, the default operations are summarized in the following table.

CDO Default Configuration Hierarchy

Software installed Defaults loaded from
CDO for Windows 2000, Outlook Express Default mail account
CDO for Windows 2000, IIS SMTP and Network News Transfer Protocol (NNTP) sites
CDO for Windows 2000, IIS, Outlook Express Microsoft Internet Information Server (IIS) and Outlook Express (sends messages through IIS pickup directory)