Error number -2147417848: Method ‘FindFirst’ of object ‘Recordset2’ failed.

Private Sub Form_BeforeUpdate(Cancel As Integer)
On Error GoTo ErrorHandler
    Dim strMsg As String
    Dim iResponse As Integer

    'Specify the mesage to display
    strMsg = "Do you wish to save the changes?" & Chr(10)
    strMsg = strMsg & "Click Yes to Save or No to Discard changes."

    'Display the msg box
    iResponse = MsgBox(strMsg, vbQuestion + vbYesNo, "Save Record?")

    'Check response
    If iResponse = vbNo Then
        'Undo the change.
        MsgBox "undo"
        DoCmd.RunCommand acCmdUndo
        'Cancel the update
        Cancel = True
    End If

    Exit Sub

ErrorHandler:
    MsgBox "Error number " & Err.Number & ": " & Err.Description
End Sub

Private Sub cboSalePicker_AfterUpdate()
On Error GoTo ErrorHandler

    Me.Recordset.FindFirst "[SaleID] = " & Str(Nz(cboSalePicker.Value, 0))

    Exit Sub
ErrorHandler:
    MsgBox "Error number " & Err.Number & ": " & Err.Description
End Sub