[Microsoft] [Диспетчер драйверов ODBC] источник данных не найден и не указан драйвер, используемый по умолчанию
Как побороть такую ошибку в этом коде.

'Defining variables
Dim cnOra As ADODB.Connection
Dim rsOra As ADODB.Recordset
Dim db_name As String
Dim UserName As String
Dim Password As String

Set cnOra = New ADODB.Connection
Set rsOra = New ADODB.Recordset

db_name = "ORCL"
UserName = "system"
Password = "manager"

'Making an ODBC connection according to ADO
cnOra.Open "DSN=" + db_name + ";UID=" + UserName + ";PWD=" _
& Password + ";"
rsOra.CursorLocation = adUseServer

'Running a query
rsOra.Open "select global_name from global_name", cnOra, adOpenForwardOnly
While Not rsOra.EOF
MsgBox rsOra![global_name]
rsOra.MoveNext
Wend