sending ICS files as an attachment using C#

static void Main(string[] args)
{
    Console.WriteLine("Welcome");
    var client = new SmtpClient("smtp.gmail.com", 587)
    {
        Credentials = new NetworkCredential("myemail@gmail.com", "password"),
        EnableSsl = true,
        Timeout =100000
    };
    Console.WriteLine("connection success");
    // Now Contruct the ICS file using string builder
    MailMessage msg = new MailMessage();
    msg.From = new MailAddress("fromemail@gmail.com", "Sender's Name");
    msg.To.Add(new MailAddress("tomail@gmail.com", "To Name"));
    msg.Subject = "Send mail with ICS file as an Attachment";
    msg.Body = "Please Attend the meeting with this schedule";
    StringBuilder str = new StringBuilder();
    str.AppendLine("BEGIN:VCALENDAR");
    str.AppendLine("PRODID:-//Schedule a Meeting");
    str.AppendLine("VERSION:2.0");
    str.AppendLine("METHOD:REQUEST");
    str.AppendLine("BEGIN:VEVENT");
    str.AppendLine(string.Format("DTSTART:{0:yyyyMMddTHHmmssZ}", DateTime.Now.AddMinutes(+10)));
    str.AppendLine(string.Format("DTSTAMP:{0:yyyyMMddTHHmmssZ}", DateTime.UtcNow));
    str.AppendLine(string.Format("DTEND:{0:yyyyMMddTHHmmssZ}", DateTime.Now.AddMinutes(+60)));
    str.AppendLine("LOCATION: CGI");
    str.AppendLine(string.Format("UID:{0}", Guid.NewGuid()));
    str.AppendLine(string.Format("DESCRIPTION:{0}", msg.Body));
    str.AppendLine(string.Format("X-ALT-DESC;FMTTYPE=text/html:{0}", msg.Body));
    str.AppendLine(string.Format("SUMMARY:{0}", msg.Subject));
    str.AppendLine(string.Format("ORGANIZER:MAILTO:{0}", msg.From.Address));
 
    str.AppendLine(string.Format("ATTENDEE;CN=\"{0}\";RSVP=TRUE:mailto:{1}", msg.To[0].DisplayName, msg.To[0].Address));
 
    str.AppendLine("BEGIN:VALARM");
    str.AppendLine("TRIGGER:-PT15M");
    str.AppendLine("ACTION:DISPLAY");
    str.AppendLine("DESCRIPTION:Reminder");
    str.AppendLine("END:VALARM");
    str.AppendLine("END:VEVENT");
    str.AppendLine("END:VCALENDAR");
 
    System.Net.Mime.ContentType contype = new System.Net.Mime.ContentType("text/calendar");
    contype.Parameters.Add("method", "REQUEST"); 
    contype.Parameters.Add("name", "Meeting.ics");
    
    // EDIT: Use the correct method to create an attachment from in-memory data:
    // msg.Attachments.Add(new Attachment(str.ToString(), contype));
    msg.Attachments.Add(Attachment.CreateAttachmentFromString(str.ToString(), contype));

    client.Send(msg);
    Console.WriteLine("Sent");
    Console.ReadLine();
}