VBAでsqlserverの主キーを取得したい。でもエラーが

    Dim cn As ADODB.Connection
    Dim cat As ADOX.Catalog
    Dim tbl As ADOX.Table
    Dim col As ADOX.Column
    Dim idx As ADOX.Index
    Dim Rs As ADODB.Recordset
    Set cn = New ADODB.Connection
    Set cat = New ADOX.Catalog
    Set Rs = New ADODB.Recordset
    Dim strRet As String
    
    cn.Open DSNName
    cat.ActiveConnection = cn
    フィールドカウント = 0
    For i = 0 To Rs.Fields.Count - 1
        If cat.Tables(テーブル名).Keys(0).Columns(i).Name _
         = Rs.Fields(i).Name Then
            DB.キー(フィールドカウント) = "○"
        End If
    Next 'i-next

    Private Sub MakiMakiLove()
        Dim hConnection As ADODB.Connection
        Set hConnection = New ADODB.Connection

        hConnection.ConnectionString = "Provider=SQLOLEDB; Data Source=Server; Initial Catalog=NorthWind; Integrated Security=SSPI;"
        On Error GoTo CatchOpenException
        Call hConnection.Open
        On Error GoTo FinallyDispose

        Dim hCatalog As ADOX.Catalog
        Set hCatalog = New ADOX.Catalog
        hCatalog.ActiveConnection = hConnection

        Dim i As Integer
        For i = 0 To hCatalog.Tables("Orders").Keys.Count - 1
            Call MsgBox(hCatalog.Tables("Orders").Keys(i).Name)
        Next i

    FinallyDispose:
        If Not hConnection Is Nothing Then
            If hConnection.State <> adStateClosed Then
                Call hConnection.Close
            End If
        End If
        Exit Sub

    CatchOpenException:
        Call MsgBox("データベース接続が確立できませんですた")
    End Sub

    Private Sub MosaMosaAA()
        Dim hConnection As ADODB.Connection
        Set hConnection = New ADODB.Connection

        hConnection.ConnectionString = _
            "Provider=SQLOLEDB;" & _
            "Data Source=Server;" & _
            "Initial Catalog=NorthWind;" & _
            "Integrated Security=SSPI;"

        On Error GoTo CatchOpenException
        Call hConnection.Open
        On Error GoTo FinallyDispose

        Dim hCatalog As ADOX.Catalog
        Set hCatalog = New ADOX.Catalog
        Set hCatalog.ActiveConnection = hConnection

        Dim hTable As ADOX.Table
        Set hTable = hCatalog.Tables("Orders")

        Dim i As Integer
        For i = 0 To hTable.Indexes.Count - 1
            Dim hIndex As ADOX.Index
            Set hIndex = hTable.Indexes(i)

            If hIndex.PrimaryKey Then
                Dim j As Integer
                For j = 0 To hIndex.Columns.Count - 1
                    Call MsgBox(hIndex.Columns(j).Name)
                Next j
            End If
        Next i

    FinallyDispose:
        If Not hConnection Is Nothing Then
            If hConnection.State <> adStateClosed Then
                Call hConnection.Close
            End If
        End If
        Exit Sub

    CatchOpenException:
        Call MsgBox("データベース接続が確立できませんですた")
    End Sub

Function IsP_key(cat As ADOX.Catalog, TblName As String, FldName As String) As Boolean
   
        Dim hTable As ADOX.Table
        Set hTable = cat.Tables(TblName)

        Dim i As Integer
        For i = 0 To hTable.Indexes.Count - 1
            Dim hIndex As ADOX.Index
            Set hIndex = hTable.Indexes(i)

            If hIndex.PrimaryKey Then
                Dim j As Integer
                For j = 0 To hIndex.Columns.Count - 1
                    If hIndex.Columns(j).Name = FldName Then
                        IsP_key = True
                    Else
                        IsP_key = False
                    End If
                    Exit Function
                Next j
            End If
        Next i

End Function

Function IsP_key(cat As ADOX.Catalog, TblName As String, FldName As String) As Boolean
   
        Dim hTable As ADOX.Table
        Set hTable = cat.Tables(TblName)
        
        IsP_key = False
        
        Dim i As Integer
        For i = 0 To hTable.Indexes.Count - 1
            Dim hIndex As ADOX.Index
            Set hIndex = hTable.Indexes(i)

            If hIndex.PrimaryKey Then
                Dim j As Integer
                For j = 0 To hIndex.Columns.Count - 1
                    If hIndex.Columns(j).Name = FldName Then
                        IsP_key = True
                    End If
                Next j
            End If
        Next i

End Function