On Error Resume Next
 
Dim con As New ADODB.Connection
Dim conStr As String
Dim oError As ADODB.Error
 
    conStr = "Driver={Microsoft ODBC for Oracle};SERVER=(DESCRIPTION=(ADDRESS=(" & _
      "PROTOCOL=TCP)(HOST=SERVER)(PORT=1521))(CONNECT_DATA=(" & _
      "SERVICE_NAME=NAME)));uid=BENUTZER;pwd=PASSW;"
 
 
    con.Open conStr
 
 
If con.Errors.Count > 0 Then
  ' alle ADO-Fehler des Connection-Objektes durchlaufen
  Dim sError As String
  For Each oError In con.Errors
    sError = sError & "Fehler: " & CStr(oError.Number) & " " & _
      oError.Description & vbCrLf & _
      "NativeError: " & oError.NativeError & vbCrLf & _
      "SQL-Status: " & oError.SQLState & vbCrLf & _
      "Quelle: " & oError.Source & vbCrLf & vbCrLf
  Next
  MsgBox sError
End If