PRB: Problems Using CDO Against an Exchange 4.x Server

ID: Q195586

The information in this article applies to:

SYMPTOMS

When you run an application that makes use of Collaboration Data Objects (CDO) as a Service on Windows NT, various functions may yield an error although the same code functions without error outside of a Service.

CAUSE

When you run CDO from a Windows NT Service, the calls are in UNICODE. Exchange Server version 4.x does not support UNICODE.

RESOLUTION

Here are two resolutions:

- Write the application to use Extended Messaging Application Programming

  Interface (MAPI) with non-UNICODE functions instead of CDO.

  -or-

  • Upgrade the Microsoft Exchange Server version 4.x to Microsoft Exchange Server version 5.0 or later.

    MORE INFORMATION

    Here are the results of running various versions of CDO from a Service against Microsoft Exchange Server 4.x:

        CDO 1.0: Cannot run from a Windows NT Service in any manner.
    
        CDO 1.1: Can run from a Windows NT Service, but is unable to Resolve a
                 Recipient's Name into an AddressEntry.
    
        CDO 1.21: Calling the Logon method of the Session object results in a
                  "MAPI_E_NO_SUPPORT" error.
    
    
    Additional query words:
    Keywords          : kbActMsg kbCDO kbCDO110 kbCDO120 kbCDO121 kbMsg 
    Version           : WINDOWS:1.1,1.2,1.21; WINNT:4.0
    Platform          : WINDOWS winnt
    Issue type        : kbprb

    Last Reviewed: November 11, 1998