dim odb as database
    Dim oRs As Recordset
    Dim SQL_Befehl As String
 
    SQL_Befehl = "SELECT * FROM Users WHERE user_name = '" &  _
      cmb_UserSelect.Text & "';"
    Set oRs = odb.OpenRecordset(SQL_Befehl)
    If oRs.RecordCount = 1 Then
        fld_UserPreName = oRs!user_name
    Else
        MsgBox "Fehler aufgetreten!"
    End If