Error correction

Hai:

When i runned this pgm i have an error user defined type not defined
can anybody correct this error

Private Sub CommandButton8_Click()
Dim Cnn As ADODB.Connection
Dim strConnect As String
Set Cnn = New ADODB.Connection

strConnect = "database=C:\Documents and Settings\Mdb\estmstr.mdb;Provider=Microsoft.Jet.OLEDB.4.0"
With Cnn
.CursorLocation = adUseClient
.Open strConnect
End With

Set Rst = New ADODB.recordset
Rst.ActiveConnection = Cnn

End Sub