Q191864: PRB: Error 743 Adding ActiveX Controls to Control Collection

Article: Q191864
Product(s): Microsoft Visual Basic for Windows
Version(s): 
Operating System(s): 
Keyword(s): kbGrpDSVB
Last Modified: 11-JAN-2001

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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 dynamically adding a large number of ActiveX controls into a Form's
Controls Collection, you receive the following:

  "Error 743. Unable to create or activate a new instance of <control
  name>."

RESOLUTION
==========

While this situation has been reported as a bug, this is an application design
problem and the best solution is "Don't do this." If you have encountered this
problem, you are probably using controls where you should be using objects.
Consider using a Class, ActiveX DLL, or ActiveX EXE to create your objects. If
you must use controls, consider using windowless controls as they are less
resource-intensive.

Keep in mind that forms with hundreds of visible controls will be confusing for
the end user. If the controls are not being displayed, then there is no reason
to use a control. ActiveX controls have a great deal of "overhead" when compared
to an object.

STATUS
======

This behavior is by design.

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

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

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

2. Choose Add Project from the File menu to add an ActiveX Control project.

3. Place an instance of UserControl1 on Form1.

4. Place a CommandButton on Form1.

5. Add the following code to the module of Form1:

        Private Sub Command1_Click()
           Dim i As Integer
           On Error GoTo trap
           For i = 1 To 1000
              Me.Controls.Add "project2.usercontrol1", "control" & i
           Next
           Debug.Print "Finished"
           Exit Sub
           trap:
           If Err.Number = 743 Then
              Debug.Print "Error 743 loading control #" & i
           End If
        End Sub

6. Run the project. You should see the message in the immediate window
  indicating that the error occurred.

Additional query words: kbDSupport kbDSD kbVBp kbVBp600 kbCtrl

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Keywords          : kbGrpDSVB 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB600Search kbVBA600 kbVB600
Issue type        : kbprb

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