CDO.Person problem

[Jason]

I am running Exchange 2003 on a Windows 2003 Active Directory.


I am trying to mailbox-enable a user account with VB.NET.
Dim person As CDO.Person
Dim mailbox As CDOEXM.IMailboxStore
person = New CDO.Person
person.DataSource.Open("...")
mailbox = person
mailbox.CreateMailbox("...")
It is failing on person = New CDO.Person. It gives me the following
error:
System.Runtime.InteropServices.COMException: COM object with CLSID


{CD000107-8B95-11D1-82DB-00C04FB1625D} is either not valid or not
registered.

The Exchange System Manager is installed on this Domain Controller and
I have manually copied cdo.dll, cdoexm.dll and cdoex.tlb to
c:\windows\system32. I regsitered cdo.dll manually, but cdoexm.dll
failed to register every time I tried.
Does anyone have any suggestions? Thanks!