Loading custom configuration files

private static XmlDocument loadConfigDocument()
{
    XmlDocument doc = null;
    try
    {
        doc = new XmlDocument();
        doc.Load(getConfigFilePath());
        return doc;
    }
    catch (System.IO.FileNotFoundException e)
    {
        throw new Exception("No configuration file found.", e);
        return null;
    }
    catch (Exception ex)
    {
        return null;
    }
}

// retrieve appSettings node

    XmlNode node =  doc.SelectSingleNode("//appSettings");

ExeConfigurationFileMap configMap = new ExeConfigurationFileMap();
configMap.ExeConfigFilename = @"d:testjustAConfigFile.config.whateverYouLikeExtension";
Configuration config = ConfigurationManager.OpenMappedExeConfiguration(configMap, ConfigurationUserLevel.None);