XL2000: Run-Time Error Using the DropDown Method with a ComboBox

When you use the DropDown method in a Microsoft Visual Basic for Applications procedure to display the list of a combo box, you may receive an error message similar to the following:

This behavior can occur when the following conditions are true:

• You have a Visual Basic procedure attached to the Click event or the Change event of a ComboBox control in a UserForm.
  
  - and -
• The Visual Basic procedure attempts to set the focus to, and then display the list of, another ComboBox control on the UserForm.

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The following example illustrates how to display the list of one ComboBox control when you make a choice in the list of another ComboBox control on a UserForm.

Populate the ListBox Directly from Worksheet Cells

1. Close and save any open workbooks, and then open a new workbook.
2. On Sheet1, type the following values:

      A1: Planes        C1: Alpha
      A2: Trains        C2: Bravo
      A3: Automobiles   C3: Charlie
   					

3. Start the Visual Basic Editor (press ALT+F11).
4. If the Properties window is not visible, click Properties Window on the View menu (or press F4).
5. On the Insert menu, click Module.
6. In the module sheet, type the following procedure:

   Sub DropDown_ComboBox()
       UserForm1.ComboBox2.DropDown
   End Sub
   					

7. On the Insert menu, click UserForm.
8. Draw a ComboBox control on the UserForm.
9. Change the following properties of the ComboBox control to the following values:

      Property          Value
      ------------------------------
      RowSource         Sheet1!A1:A3
   					

10. Double-click the ComboBox to open the code window.
11. In the module, type the following code for the ComboBox Click event:

    Private Sub ComboBox1_Click()
        Application.OnTime Now, "DropDown_ComboBox"
    End Sub
    					

12. Draw another ComboBox control on the UserForm.
13. Change the following properties of the ComboBox control to the following values:

       Property          Value
       ------------------------------
       RowSource         Sheet1!C1:C3
    					

14. Run the UserForm.

When you click an item in the ComboBox1 list, the ComboBox2 list is automatically displayed.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

For more information about using the ComboBox control, in the Visual Basic Editor, click Microsoft Visual Basic Help on the Help menu, type comboboxcontrol in the Office Assistant or the Answer Wizard, and then click Search to view the topic.

For more information about using the DropDown method, in the Visual Basic Editor, click Microsoft Visual Basic Help on the Help menu, type dropdown method in the Office Assistant or the Answer Wizard, and then click Search to view the topic.