DOCUMENT:Q199942  24-JUL-2002  [visualc]
TITLE   :FIX: Tstcon32.exe Cannot Invoke Method with BSTR* Parameter Type
PRODUCT :Microsoft C Compiler
PROD/VER::6.0
OPER/SYS:
KEYWORDS:kbole kbActiveX kbCOMt kbContainer kbCtrl kbMFC kbMiscTools kbVC600bug kbDSupport kbGrp

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The information in this article applies to:

 - The Microsoft Foundation Classes (MFC), used with:
    - Microsoft Visual C++, 32-bit Enterprise Edition, version 6.0 
    - Microsoft Visual C++, 32-bit Professional Edition, version 6.0 
    - Microsoft Visual C++, 32-bit Learning Edition, version 6.0 
    - Microsoft Visual C++.NET (2002) 
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SYMPTOMS
========

The ActiveX Control Test Container (version 6.0.8063) that ships with Visual C++
6.0 and Visual C++.NET fail to invoke a method of an MFC ActiveX control that
has BSTR* parameter type.

CAUSE
=====

Microsoft has confirmed that this is a bug in Visual C++ 6.0 and Visual C++.NET
ActiveX Control Test Container.

RESOLUTION
==========

To work around this issue:

 - Use containers such as Visual Basic.

 - Use LPCTSTR as the parameter type.

STATUS
======

Microsoft has confirmed that this is a problem in the Microsoft products that
are listed at the beginning of this article.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

1. Use the MFC ActiveX ControlWizard to create an ActiveX control project.

2. Add a method to the ActiveX control as follows:

   void CMyControl::Test(BSTR FAR* Par1)
         {
            // TODO: Add your dispatch handler code here
            AfxMessageBox("In Test");
            return 0;
         }

3. Build the control project.

4. Insert the control to the ActiveX Control Test Container of Visual C++ 6.0 or
   Visual C++.NET.

5. Invoke the Test() method in the ActiveX Control Test Container and the
   message box does not appear. The following error is displayed in the output
   window of Visual C++:

   First-chance exception in TSTCON32.EXE (KERNEL32.DLL): 0xE06D7363: Microsoft
   C++ Exception. Warning: automation argument coercion failed. First-chance
   exception in TSTCON32.EXE (KERNEL32.DLL): 0xE06D7363: Microsoft C++

Additional query words:

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Keywords          : kbole kbActiveX kbCOMt kbContainer kbCtrl kbMFC kbMiscTools kbVC600bug kbDSupport kbGrpDSMFCATL kbNoUpdate 
Technology        : kbAudDeveloper kbMFC
Version           : :6.0
Issue type        : kbbug
Solution Type     : kbfix

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