DOCUMENT:Q216278  28-JUN-2001  [visualc]
TITLE   :BUG: Unspecified Error When Running VB Program Hosting ATL Ctrl
PRODUCT :Microsoft C Compiler
PROD/VER:WINDOWS:3.0,6.0
OPER/SYS:
KEYWORDS:kbActiveX kbCOMt kbContainer kbCtrl kbCtrlCreate kbPersistSt kbVBp600 kbATL300bug kbGrp

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The information in this article applies to:

 - The Microsoft Active Template Library (ATL) 3.0, included with:
    - Microsoft Visual C++, 32-bit Editions, 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 you run a Visual Basic program that contains an ATL ActiveX control, you
may get the following error message:

   System Error &H80004005 (-2147467259). Unspecified error.

CAUSE
=====

If you created the control using the ATL Object Wizard and added the "HWND"
option in the Stock Properties tab, you will get an entry in the .IDL for a
[propget] function for the "Window" stock property.

In addition, the property map will contain a PROP_ENTRY(HWND...) macro. When the
control is first initialized, the persistence code will go through the property
map and call the [propput] functions for each entry via ITypeInfo::Invoke().
Because there is no [propput] function in the .IDL for the Window property, the
type library won't have this function, and ITypeInfo::Invoke() will fail.

RESOLUTION
==========

Persisting an HWND doesn't make sense; just comment out the PROP_ENTRY(HWND...)
macro in the property map. To prevent this line from being added in the future,
remove the following line from Control.h in \Program Files\Microsoft Visual
Studio\Common\MSDev98\Template\ATL:

   [!if=(SP_HWND, "TRUE")]	PROP_ENTRY("HWND", DISPID_HWND, CLSID_NULL)[!endif]

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

Additional query words:

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Keywords          : kbActiveX kbCOMt kbContainer kbCtrl kbCtrlCreate kbPersistSt kbVBp600 kbATL300bug kbGrpDSMFCATL kbbuglist
Technology        : kbVCsearch kbAudDeveloper kbATLsearch
Version           : WINDOWS:3.0,6.0
Issue type        : kbbug
Solution Type     : kbpending

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