PRB: "MAPI_E_NO_SUPPORT" Calling Session.Logon on Windows 95/98

ID: Q194069

The information in this article applies to:

Collaboration Data Objects (CDO), versions 1.0a, 1.1, 1.2, 1.21

SYMPTOMS

When calling the Logon method of the Session object on a system running Windows 95 or Windows 98, the following error may occur:

MAPI_E_NO_SUPPORT

CAUSE

One or more elements of the Windows Messaging Subsystem installed on the computer are out of date.

RESOLUTION

WARNING: Using the Registry Editor incorrectly can cause serious, system- wide problems that may require you to reinstall Windows to correct them. Microsoft cannot guarantee that any problems resulting from the use of Registry Editor can be solved. Use this tool at your own risk.

IMPORTANT: Before you edit the registry, make sure you understand how to restore it if a problem occurs. For information about how to do this, view the "Restoring the Registry" Help topic in Regedit.exe or the "Restoring a Registry Key" Help topic in Regedt32.exe.

For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it.

Usually an uninstall followed by a reinstall of the existing Windows Messaging Subsystem (typically, a messaging client such as Microsoft Outlook) suffices. However, if you encounter a situation where it does not, the following steps should address the issue.

Using the registry editor, (Regedit.exe), search the registry for one or more of the following keys:
```
      HKEY_CLASSES_ROOT\ActMsg.Session
      HKEY_CLASSES_ROOT\CLSID\{3FA7DEB3-6438-101B-ACC1-00AA00423326}
      HKEY_CLASSES_ROOT\MAPI.Folder
      HKEY_CLASSES_ROOT\MAPI.Message
      HKEY_CLASSES_ROOT\MAPI.Session
      HKEY_CLASSES_ROOT\MAPI.Session.1
      HKEY_CLASSES_ROOT\TypeLib\{3FA7DEB3-6438-101B-ACC1-00AA00423326}
      HKEY_LOCAL_MACHINE\SOFTWARE\Classes\ActMsg.Session 
```
Upon finding a match, delete the key. However, be careful to only remove the keys that relate to messaging.

NOTE: Some of these keys include subkeys. Deletion of the top-level key also deletes the subkeys. After double-checking that the top-level key matches one of the keys noted above, it should be OK to also delete any subkeys.

Install the Microsoft Exchange 5.0 (or later) Client or Server, or Microsoft Outlook Client version 8.01 (or later - use Corporate Workgroup mode for Outlook 98). This installs an updated Windows Messaging Subsystem as well as Collaboration Data Objects (CDO) version 1.1 or higher depending on what product is installed. The name of the CDO Library changes from one version to the next. Therefore, be sure to check that your project references match the name of the file installed by the product from which you get CDO.

Run your application. You should be able to logon without the error message occurring.

REFERENCES

For more information on names and versions of CDO, please see the following article in the Microsoft Knowledge Base:

Q171440 Where to Acquire the Collaboration Data Objects Libraries

Additional query words: kbDSupport kbCDO kbMsg kbCDO100a kbCDO110 kbCDO120 kbCDO121 kbOLE

Keywords : kbCDO100a kbCDO110 kbCDO120 kbCDO121 kbMAPI kbMsg kbWinOS95 kbWinOS98 kbGrpMsg
Version : WINDOWS:1.0a,1.1,1.2,1.21
Platform : WINDOWS
Issue type : kbprb