The Collaboration Data Objects libraries implement messaging and collaboration functionality in a custom application. This article contains information on where these libraries can  be found.
The  information in this article applies to:
  • Collaboration Data Objects (CDO), versions 1.1, 1.2, 1.21
  • Collaboration Data Objects (CDO) for NTS, version 1.2
  • Microsoft Collaboration Data Objects for Windows 2000
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 Microsoft Exchange Server.
Collaboration Data Objects for NTS (CDONTS) is a Simple Mail Transfer Protocol (SMTP) 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 significant improvement 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:
Version Messaging Library (MSG) Rendering Library (RND) CDO for NTS (NTS) CDO for Windows 2000 (SYS)
1.1 Olemsg32.dll Amhtml.dll Cdonts.dll N/A
1.2 Cdo.dll Cdohtml.dll Cdonts.dll N/A
1.21 Cdo.dll Cdohtml.dll N/A N/A
6.0 N/A N/A N/A Cdosys.dll
You can get these files through the following product installations:
  • CDO 1.21 was previously available for download in a redistributable format. However, the redistributable version of the CDO is no longer available. The CDO must be installed by another product, such as Microsoft Outlook or Exchange.
  • Outlook 2000 installation does not include the CDO component by default. You must choose the CDO component during installation.
  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
Windows  2000 N N N N N N N N N Y

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Last Modified On: December 10, 2016