KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q173261: FIX: Dialog in InitInstance Doesn’t Process WM_DDE_INITIATE

Article: Q173261
Product(s): Microsoft C Compiler
Version(s): 2.0,2.1,2.2,4.0,4.1,4.2,5.0
Operating System(s): 
Keyword(s): kbnokeyword kbMFC kbVC200 kbVC210 kbVC220 kbVC400 kbVC410 kbVC420 kbVC500 kbVC600fix kb
Last Modified: 17-JUL-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- The Microsoft Foundation Classes (MFC), used with:
   - Microsoft Visual C++, 32-bit Editions, versions 2.0, 2.1, 2.2, 4.0, 4.1 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 4.2 
   - Microsoft Visual C++, 32-bit Professional Edition, version 4.2 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

When you try to start an application that contains a modal dialog function, such
as CDialog::DoModal, AfxMessageBox, or MessageBox, that is called from the
CWinApp derived class' InitInstance function by double-clicking on the
application from the Windows 95 Explorer, selecting the saved document from the
Start Menu or double-clicking on it from File Manager, one of the following may
happen:

- It may work fine if built with Visual C 2.x running under Windows NT 3.5x and
  later.

-or-

- The dialog or message box may come up, but the application's main window may
  not come up, and the process is now hung, and can only be terminated by
  PVIEW.

-or-

- The following error message box may be displayed:

  Cannot find the file <path\filename> (or one of its components). Make
  sure the path and filename are correct and that all required libraries are
  available.

  And, symptom number 2 may also occur.

CAUSE
=====

When you launch an application in File Manager or Windows Explorer, a
WM_DDE_INITIATE is supposed to be handled by the CWinApp and CFrameWnd
OnDDEIntitiate handlers. A call to CDialog::DoModal, AfxMessageBox, or
MessageBox interferes with the ability for the MFC framework to handle these
messages correctly.

RESOLUTION
==========

It has been determined that this behavior is by design and that it is not
recommended to place any of these calls within the CWinApp::InitInstance. Any
password dialogs or dialog based components which need to be displayed in the
InitInstance should be of the modeless type. This does not apply to a dialog
based application or an SDI application.

STATUS
======

This problem was corrected in Visual C++ version 6.0.

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

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

1. Create an AppWizard Multiple Document Application, specifying a file
  extension to associate with the application.

2. Call a modal dialog function such as CDialog::DoModal, AfxMessageBox, or
  MessageBox from the CWinApp derived class' InitInstance function.

3. Run the application, dismiss the dialog or message box, and save the
  document.

4. Start the application by:

  1. Double-clicking the application from the Windows 95 Explorer.

  -or-

  2. Selecting the saved document from the Start Menu

  -or-

  3. Double-clicking the application from File Manager.

REFERENCES
==========

For related information, please see the following article in the Microsoft
Knowledge Base:

  Q172336 PRB: Assertion Launching Program with Tip of Day & Splash Screen

Additional query words: explorer start file manager

======================================================================
Keywords          : kbnokeyword kbMFC kbVC200 kbVC210 kbVC220 kbVC400 kbVC410 kbVC420 kbVC500 kbVC600fix kbGrpDSMFCATL kbNoUpdate 
Technology        : kbAudDeveloper kbMFC
Version           : :2.0,2.1,2.2,4.0,4.1,4.2,5.0
Issue type        : kbbug
Solution Type     : kbfix

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.