DOCUMENT:Q246233  26-JUL-2001  [vbwin]
TITLE   :FIX: Nested UserControl DataSource Property Causes Crash
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:WINDOWS:6.0
OPER/SYS:
KEYWORDS:kbCtrlCreate kbVBp kbVBp600bug kbGrpDSVB kbDSupport kbVS600sp4fix kbVS600sp5fix

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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
========

Visual Basic generates an Access Violation error when you select the DataSource
property of a TextBox control that is placed on a UserControl. This only happens
if the UserControl has been placed on a second UserControl in the same project.
On computers that do not have Visual Studio Service Pack 3 installed, you may
not get the Access Violation error. However, the control disappears. If you have
a Data control on the UserControl that contains the TextBox, you always get the
crash.

RESOLUTION
==========

To resolve this problem, install Visual Studio 6.0 Service Pack 4.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug was corrected in the latest service pack for
Visual Studio 6.0.

For additional information about Visual Studio service packs, click the article
numbers below to view the articles in the Microsoft Knowledge Base:

   Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

   Q194295 HOWTO: Tell That a Visual Studio Service Pack Is Installed

You can download the latest Visual Studio service pack from the following
Microsoft Web site:

   Visual Studio Product Updates
   (http://msdn.microsoft.com/vstudio/downloads/updates.asp)

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

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

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

2. From the Project menu, choose Add User Control to add a UserControl
   (UserControl1) to the project.

3. Place a TextBox and a Data control on UserControl1.

   NOTE: The Access Violation also happens without the Data control on computers
   that have Visual Studio Service Pack 3.

4. Close UserControl1.

5. Add a second UserControl (UserControl2) to the project.

6. Place UserControl1 on UserControl2.

7. Close UserControl2 and Form1.

8. Open UserControl1.

9. Select Text1 on UserControl1, and, in the Properties window, click on the
   DataSource property. The control might disappear. If so, repeat the preceding
   two steps and Visual Basic generates the Access Violation error.

Additional query words: sp4

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Keywords          : kbCtrlCreate kbVBp kbVBp600bug kbGrpDSVB kbDSupport kbVS600sp4fix kbVS600sp5fix 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB600Search kbVB600
Version           : WINDOWS:6.0
Issue type        : kbbug
Solution Type     : kbfix

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