DOCUMENT:Q118767  11-JAN-2001  [vbwin]
TITLE   :PRB: Custom Control or Library Not Working with VB 4.0
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Visual Basic Standard Edition for Windows, version 4.0 
 - Microsoft Visual Basic Professional Edition for Windows, version 4.0 
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SYMPTOMS
========

It is possible that a custom control or dynamic link library that used
undocumented features of Visual Basic version 3.0 will not work correctly in
Visual Basic version 4.0.

CAUSE
=====

Visual Basic version 4.0 is designed to be backward compatible. However, some
third-party companies have based custom controls and routines on undocumented
features in Visual Basic version 3.0. The internal structure of Visual Basic has
changed significantly for version 4.0. Therefore, controls and libraries based
on undocumented features or undocumented internal structures may no longer work.

RESOLUTION
==========

If you find that your third-party custom control or library that worked in
Visual Basic version 3.0 is not working correctly in Visual Basic version 4.0,
please contact the third-party add-on manufacturer. The company may have an
updated version designed to work with Visual Basic version 4.0.


Additional query words: 4.00 vbx incompatible incompatibility vb4all vb4win

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Keywords          :  
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB400Search kbVB400
Issue type        : kbprb

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