<Item> is not a valid control type (Error 720)

Only valid ActiveX components can be assigned as controls on forms. This error has the following cause and solution:

• You attempted to assign an ActiveX component as a control on a form that isn't recognized as a valid control component.

  See the Help topics for building ActiveX controls to determine what constitutes an acceptable control.

For additional information, select the item in question and press F1 (in Windows) or HELP (on the Macintosh).