mdb升迁adp后提示对象变量或with块变量未设置,请回答

Private Sub ctExplorer1_lbItemClick(ByVal nList As Integer, ByVal nItem As Integer)

On Error GoTo TC_Err

    Dim Func As String, mdl As String
With ctExplorer1
    '点击时自动打开相应的功能,相应的功能 已经保存在项目的lbItemCargo属性中
    If Not IsNull(.lbItemCargo(nList, nItem)) Then
       mdl = .lbItemCargo(nList, nItem)
       '调用openCmd打开相应功能(窗体或报表或函数)
       OpenCmd mdl
       Exit Sub
    End If
End With

    Exit Sub
TC_Err:
    glMessageBox "错误:" & err.Description
    Exit Sub
End Sub