VB Forum / COM / December 2003

This some down to the Simple MAPI specification. If all the other companies
confirm to using simple mapi then you would not have this problem.
Unfortunately 3rd party have their own propriertary mapi formats and hence
this could be why you are seeing the problem.

The Simple Messaging Application Programming Interface
         (MAPI) is a set of messaging functions that help you create
messaging-enabled
         applications. It is a subset of MAPI, which provides complete access to
         messaging and information exchange systems.

With Simple MAPI, you
         can:

- Log on and off the messaging system.

- Find and read messages.

- Address new messages by adding recipients to the messages.

- Add attachments to messages.

- Save and send messages.

Simple MAPI functions are available for Microsoft C languages
         and Microsoft Visual Basic. This article discusses extensions to the
Visual
         Basic implementation to support Visual Basic for Applications. The
Simple MAPI
         function names, parameters, and return values are identical for both
Visual
         Basic and Visual Basic for Applications.

NOTE: For information on
         the C or Visual Basic implementations of Simple MAPI, please see the
Microsoft
         Mail Technical Reference.

Requirements for Simple MAPI for Visual Basic for Applications
--------------------------------------------------------------

To use Simple MAPI for Visual Basic for Applications, you need:
         

1. An application that includes Visual Basic for Applications,
                such as:

    -    Microsoft Excel for Windows version 5.0 or
                            later

    -    Microsoft Project for Windows version 4.0 or
                            later

    -    Microsoft Windows for Workgroups version 3.1 or
                            later -or-

2. Microsoft Windows version 3.1 or later and Microsoft Mail for PC
  Networks version 3.0 or later.

You can use the Mail client application from Microsoft Windows
         for Workgroups with the Microsoft Windows for Workgroups post office,
the
         Microsoft Mail for PC Networks post office, Microsoft Mail Remote, or
with a
         variety of MAPI-compatible messaging service providers.

NOTE: To use
         Simple MAPI with earlier versions of Microsoft Excel or Microsoft
Project, use
         the Workgroup Extensions for Microsoft Excel or the Workgroup
Extensions for
         Microsoft Project. These extension libraries are available in Microsoft
Office
         Developer's Kit.

Components of Simple MAPI for Visual Basic for Applications
-----------------------------------------------------------

The Simple MAPI for Visual Basic for Applications library
         includes the following four files:

    VBAMAPI.DLL    Simple MAPI for Visual Basic for Applications run-time
                   library
   
    VBAMAPI.TXT    Simple MAPI function and variable declarations
   
    VBAMAPI2.TXT   Additional function declarations for logon, logoff, and
                   error checking
   
    MAPIVB.HLP     Documentation for Simple MAPI functions for Visual Basic
                   and Visual Basic for Applications
                   
The following file is available for download from the Microsoft Download
Center:

   
http://download.microsoft.com/download/excel50mac/samp45/1/WIN98/EN-US/vbama
pi.exe: Vbamapi.exe
For
            additional information about how to download Microsoft Support files,
click the
            following article number to view the article in the Microsoft Knowledge
Base:

    KBLink:119591.Article.EN-US: How to Obtain Microsoft Support Files from
    Online Services

Microsoft scanned this file for viruses. Microsoft used the most
            current virus-detection software that was available on the date that
the file
            was posted. The file is stored on security-enhanced servers that help to
            prevent any unauthorized changes to the file.
         

Installing Simple MAPI for Visual Basic for Applications
--------------------------------------------------------

To use Simple MAPI for Visual Basic for Applications, copy
         VBAMAPI.DLL to the Windows System directory (usually
C:\WINDOWS\SYSTEM). All
         users require this file. VBAMAPI.DLL is a run-time library that you can
freely
         copy to any system. Your users may require client, node, or end-user
licenses
         for the messaging system you use.

Only developers require the other
         files. You can copy them to any directory.

Developing Applications with Simple MAPI for Visual Basic for Applications
--------------------------------------------------------------------------

To develop messaging applications with Simple MAPI for Visual
         Basic for Applications:
         

1. Include the Simple MAPI for Visual Basic for Applications
  declarations in your module.

2. Include correct logon and logoff functions in your module.

3. Refer to the Simple MAPI documentation for information about Simple
  MAPI data types and functions.

Including Simple MAPI Declarations
----------------------------------

VBAMAPI.TXT includes the required declarations for Simple MAPI
         data types, functions and constants. You must include these
declarations in
         your module to use Simple MAPI.

Microsoft Project version 4.0
         already includes these declarations in the global file (GLOBAL.MPT). For
         Microsoft Excel version 5.0, you must add a module for the Simple MAPI
         declarations.

To add a module in Microsoft Excel:

1. Open a new or existing workbook.

2. From the Insert menu, choose Macro Module.

3. Move the insertion point to the end of the new module (after any
  Option statements), and choose File from the Insert menu.

4. In the Insert File dialog box, choose VBAMAPI.TXT.

Logging On and Off Mail Sessions
--------------------------------

Microsoft Excel and Microsoft Project both include MailLogon and
         MailLogoff methods, so you should use these methods instead of the
Simple MAPI
         MAPILogon and MAPILogoff functions.

In addition, Microsoft Excel and
         Microsoft Project provide a MailSession property that maintains the
         application's mail session, and the MailSystem property that identifies
the
         current messaging system.

The file VBAMAPI2.TXT includes functions
         that use these built-in mail methods and properties. You can insert the
example
         code listed in this section into your macro.

Logging On a Mail Session
-------------------------

You should add the following DoMailLogon function to your macro
         to log on a mail session. Because the MailLogon method logs off any
existing
         session before logging on the new session, the function first checks to
see
         whether a valid session already exists.
         

<<\**

For Outsourcer Only:
===================

kbon

**/>>

   
    ''********************************************************************
    'DoMailLogon() uses the application's mail logon method
    'rather than MAPILogon()
    '********************************************************************
    Function DoMailLogon() As Long
      ' Log on to Mail if not logged on already:
      If IsNull(Application.MailSession) Then
         Application.MailLogon
      End If
      ' Convert the hex string session handle to a long integer:
      DoMailLogon = CLng("&h" & Application.MailSession)
    End Function
                   

<<\**

For Outsourcer Only:
===================

kboff

**/>>

Logging Off a Mail Session
--------------------------

Add the following DoMailLogoff function to your macro to log off
         the mail session. This function only logs off if a valid mail session
actually
         exists.
         

<<\**

For Outsourcer Only:
===================

kbon

**/>>

   
    '********************************************************************
    'DoMailLogoff uses the application's mail logoff method
    'rather than MAPILogoff()
    '********************************************************************
    Sub DoMailLogoff()
      ' Logoff from Mail if logged on:
      If Not IsNull(Application.MailSession) Then
         Application.MailLogoff
      End If
    End Sub
                   

<<\**

For Outsourcer Only:
===================

kboff

**/>>

Simple MAPI Documentation
-------------------------

The MAPIVB.HLP file provides documentation for Simple MAPI for
         both Visual Basic and Visual Basic for Applications. This documentation
is also
         available in the Microsoft Mail Technical Reference. You can refer to
this
         documentation to see what MAPI functions you need to use in your own
macros and
         how to call them.

How to Determine if MAPI Is Available
-------------------------------------

If you plan to distribute your macro to users of diverse
         messaging systems, your macro should determine if MAPI is available
before
         using any Simple MAPI functions. In Microsoft Excel and Microsoft
Project, the
         MailSystem property identifies the user's current messaging system.

How to Display Simple MAPI Errors
---------------------------------

The file VBAMAPI2.TXT includes the GetMAPIErrorText function,
         which you can use to convert MAPI integer error codes to strings.

Alternatives to Simple MAPI
---------------------------

Not all applications need the full functionality of Simple MAPI.
         Microsoft Excel and Microsoft Project provide built-in messaging
functionality
         that is easier to use for less complicated tasks. In Excel, you can use
the
         SendMail method of the Workbook object and the RoutingSlip object to
send files
         to users. In Microsoft Project, the MailSend and MailRoutingSlip
methods of the
         Application object offer similar functionality.

Microsoft Excel and
         Microsoft Project have built-in messaging functionality that works with
MAPI
         and with Vendor Independent Messaging (VIM) systems; while the Simple
MAPI
         functions require a MAPI-compatible messaging system.

Paresh Joshi
UK Developer Support
This posting is provided "AS IS" with no warranties, and confers no rights.