Dim UnitForm() as new frmUnit Dim UnitNumber as long Private Sub MDIForm_Click() ' Program unloaded fine before I clicked to make a new unit form ' It will give an illegal operation now ' Add a new form to our form array UnitNumber = UnitNumber + 1 ReDim Preserve UnitForms(0UnitNumber) As New frmUnit UnitForms(UnitNumber).Show End Sub