DOCUMENT:Q233398  11-JAN-2001  [vbwin]
TITLE   :PRB: Common Dialog ShowHelp Method does not Work with CHM Files
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:WINDOWS:6.0
OPER/SYS:
KEYWORDS:kbCmnDlg kbVBp600 kbGrpDSVB kbDSupport

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The information in this article applies to:

 - Microsoft Visual Basic Learning Edition for Windows, version 6.0 
 - Microsoft Visual Basic Professional Edition for Windows, version 6.0 
 - Microsoft Visual Basic Enterprise Edition for Windows, version 6.0 
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SYMPTOMS
========

When attempting to display a Help file using the Microsoft Common Dialog Control
6.0, the following error message is displayed:

   The filename file is not a Windows Help file, or the file is corrupted.

CAUSE
=====

The ShowHelp method launches WinHelp32.exe, which does not support HTML based
help files.

RESOLUTION
==========

To open an HTML based help file from Visual Basic it is necessary to call the
HtmlHelp API function.

STATUS
======

This behavior is by design.

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

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

1. Open a new Visual Basic Standard EXE project. Form1 is created by default.

2. From the Project menu, choose Components and then select "Microsoft Common
   Dialog Control 6.0". Next, click OK.

3. Site a Common Dialog control on Form1.

4. Add the following code to the General Declarations section of Form1:

      Private Sub Form_DblClick()
         CommonDialog1.HelpFile = "c:\winnt\help\vbsetup.chm"
         CommonDialog1.HelpCommand = cdlHelpContents
         CommonDialog1.ShowHelp
      End Sub

5. Modify the path and file name in the second line of code to point to an
   existing .chm file on your system.

6. Run the application and double-click Form1. The error message described in
   the SYMPTOMS section occurs.

REFERENCES
==========

Visual Basic Online Help; search on: "ShowHelp" For more information, please see
the following article in the Microsoft Knowledge Base:

   Q183434: HOWTO: Use HTML Help API in a Visual Basic Application

Additional query words:

======================================================================
Keywords          : kbCmnDlg kbVBp600 kbGrpDSVB kbDSupport 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB600Search kbVBA600 kbVB600
Version           : WINDOWS:6.0
Issue type        : kbprb

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