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Where to acquire the CDO Libraries (all versions)

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The Collaboration Data Objects (all versions) Libraries are used to implement Messaging and Collaboration functionality into a custom application. This article contains information on where these libraries can be found.

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The dynamic-link libraries (DLLs) for CDO (1.1, 1.2, 1.21) and CDO Rendering (1.1, 1.2) are MAPI client object libraries. As such, they require MAPI and service providers (for example, the same service providers as with Microsoft Exchange Server).

Collaboration Data Objects for NTS (CDONTS) is a Simple Mail Transfer Protocol (SMTP) based Messaging offering, which is part of the overall CDO (1.1, 1.2) Library, but is not MAPI dependent.

Collaboration Data objects for Windows 2000 (CDOSYS), is a quantum leap in SMTP Messaging over CDONTS. CDOSYS provides for rich content through extensive MIME support.

The names of these files vary depending on the version of CDO as noted in the following table:

Version Messaging Lib
Rendering Lib
CDO for Win2K
v1.1 Olemsg32.dll Amhtml.dll Cdonts.dll n/a
v1.2 Cdo.dll Cdohtml.dll Cdonts.dll n/a
v1.21 Cdo.dll Cdohtml.dll n/a n/a
v6.0 n/a n/a n/a Cdosys.dll
These files can be obtained through the following product installations:
    v1.1     v1.2     v1.21   v6.0
Outlook 8.00 N N N N N N N N N N
Exchange 5.0 Client Y N N N N N N N N N
Outlook 8.01-8.03 Y N N N N N N N N N
Exchange 5.0 Server Y Y Y N N N N N N N
IIS 4.0 N N Y N N N N N N N
Outlook 98 N N N N N N Y N N N
Exchange 5.5 Server N N N Y Y Y N N N N
Exchange 5.5 Server SP1 N N N N Y Y Y N N N
Exchange 5.5 Server SP2 N N N N Y Y Y N N N
Outlook 2000 N N N N N N Y N N N
Outlook 2002 N N N N N N Y N N N
Outlook 2003 N N N N N N Y N N N
Windows 2000 N N N N N N N N N Y
Exchange 2000 N N N N N N Y Y N N
Exchange 2000 SP1 N N N N N N Y Y N N
Exchange 2000 SP2 N N N N N N Y Y N N
Exchange 2000 SP3 N N N N N N Y Y N N
Windows 2003 N N N N N N N N N Y
Exchange 2003 N N N N N N Y N N N

Starting with Microsoft Exchange Server 2007 Beta 2, neither the Messaging API (MAPI) client libraries nor CDO 1.2.1 are included. Therefore, functionality is missing, and many application depend on this functionality. Microsoft Exchange MAPI and CDO 1.2.1 provide access to these APIs. These APIs provide access to the contents of MAPI stores.

Note Because this version of CDO is included with the Exchange 2003, we do not support installing this version on a computer that has Outlook installed. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

266418 Microsoft does not support installing Exchange Server components and Outlook on the same computer
For computers running Outlook 2010, using CDO is not supported. For more information, please see the following Microsoft Knoowledge Base article:
Note CDO version 1.2.1 refers to the version of the API not the version of the DLL which implements the API. The DLL contained in the Outlook 2007 CDO download is version 6.5. This is not an update to CDOSYS which is referred in this article as version 6.0.

When using Exchange to install CDO 1.21, you can use one of the following methods to install:
  • Install Exchange Server (Exchange 5.5, 2000, and 2003)
  • Install only the Exchange Administrator (or Exchange System Manager) utility (Exchange 5.5, 2000, and 2003)
  • Install Outlook Web Access (OWA - Exchange 5.5 only)
After the installation, you may have to manually register Cdo.dll by using Regsrv32 (that is, regsrv32.exe full path and file name of CDO.DLL). For Exchange System Manager installations, you must copy Cdo.dll from the installation media to the %Program Files%/Exchsrvr/bin directory before you register Cdo.dll by using Regsrv32.exe.

By default, Outlook installations do not include the CDO 1.2x component. When you view the options for Office or Outlook setup, CDO is listed under the options for Outlook.

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Keywords: kb, kbmsg, kbinfo, kbdswmessaging2003swept, kbdswlhwrapup, kbdswlhapplies

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Article Info
Article ID : 171440
Revision : 6
Created on : 9/29/2020
Published on : 9/29/2020
Exists online : False
Views : 268