Array already has a control at index 'item'

Possible causes:

         You tried to change the index to a number that is already used by this control array.  To determine which indexes have already been assigned, select the Index property on the Properties bar for each control array element.  The assigned index appears in the Settings text box.

         You tried to change the CtlName of a control in an array to the name of a control array already using this index.