SMTP server settings on local machine to use automatic email service in ASP.Net using C#

<appSettings>
<add key="SMTP" value="hostname.com"/>
<add key="FROMEMAIL" value="myemailadderss@yahoo.com"/>
<add key="FROMEPWD" value="ur email pwd">
<add key="PORT" value="25">
</appSettings>

protected bool Send(string To, string From, string Subj, string Msg)
    {
        try
        {
            string mFrom = From.ToString().Trim();
            string mTo = To.ToString().Trim();
            string mSubject = Subj.ToString().Trim();
            string mMsg = Msg.ToString().Trim();

            string mMailServer = ConfigurationManager.AppSettings.Get("SMTP");
            int mPort = Convert.ToInt32(ConfigurationManager.AppSettings.Get("PORT"));

            MailMessage message = new MailMessage(mFrom, mTo, mSubject, mMsg);
            SmtpClient mySmtpClient = new SmtpClient(mMailServer, mPort);
            // mySmtpClient.Credentials = new System.Net.NetworkCredential(ConfigurationManager.AppSettings["FROMEMAIL"], ConfigurationManager.AppSettings["FROMPWD"]);
            //mySmtpClient.EnableSsl = true;
            message.Priority = MailPriority.High;
            mySmtpClient.UseDefaultCredentials = true;
            mySmtpClient.Send(message);
            return true;
        }
        catch (Exception ex)
        {
            return false;
        }
    }