What's Windows version? What line of code generates the error?

>I'm trying to use CDO to send emails, and I'm getting the following error message:
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> CDO.Configuration.1 Class not registered
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>In fact, what is bizarre is that I do succeed sending mails, but I can't customize any configuration (like server, login, password, etc). The error doesn't happens when a create the object, so, when the program runs the line with CREATEOBJ("CDO.Configuration") it does create the object. The error appears when I try to effectively use this object.
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