Mailbox exists c#

private static void Main(string[] args)
{            
  var gMail = IsEmailAccountValid("gmail-smtp-in.l.google.com", "aa.aa@gmail.com");
  Console.WriteLine($"Gmail account is valid - {gMail.ToString()}");

  var live = IsEmailAccountValid("live-com.olc.protection.outlook.com", "aa.aa@live.com");
  Console.WriteLine($"Live account is valid - {live.ToString()}");
}

private static byte[] BytesFromString(string str)
{
  return Encoding.ASCII.GetBytes(str);
}

private static int GetResponseCode(string ResponseString)
{
  return int.Parse(ResponseString.Substring(0, 3));
}

private static bool IsEmailAccountValid(string tcpClient, string emailAddress)
{
  TcpClient tClient = new TcpClient(tcpClient, 25);
  string CRLF = "\r\n";
  byte[] dataBuffer;
  string ResponseString;
  NetworkStream netStream = tClient.GetStream();
  StreamReader reader = new StreamReader(netStream);
  ResponseString = reader.ReadLine();

  /* Perform HELO to SMTP Server and get Response */
  dataBuffer = BytesFromString("HELO Hi" + CRLF);
  netStream.Write(dataBuffer, 0, dataBuffer.Length);
  ResponseString = reader.ReadLine();
  dataBuffer = BytesFromString("MAIL FROM:<YourGmailIDHere@gmail.com>" + CRLF);
  netStream.Write(dataBuffer, 0, dataBuffer.Length);
  ResponseString = reader.ReadLine();

  /* Read Response of the RCPT TO Message to know from google if it exist or not */
  dataBuffer = BytesFromString($"RCPT TO:<{emailAddress}>" + CRLF);
  netStream.Write(dataBuffer, 0, dataBuffer.Length);
  ResponseString = reader.ReadLine();
  var responseCode = GetResponseCode(ResponseString);

  if (responseCode == 550)
  {
    return false;
  }

  /* QUITE CONNECTION */
  dataBuffer = BytesFromString("QUITE" + CRLF);
  netStream.Write(dataBuffer, 0, dataBuffer.Length);
  tClient.Close();
  return true;
}

Source: stackoverflow.com

Similar codes

12 votes152 views2 answers
Angular No provider for HttpClient
TypeScript
12 votes139 views5 answers
Font awesome angular
TypeScript
1 vote132 views1 answer
Macos fonts download for linux ubuntu
TypeScript
9 votes131 views2 answers
Array contains typescript
TypeScript
1 vote134 views1 answer
Ts object field from variable
TypeScript
1 vote93 views1 answer
Take commits from main and move to a new branch
TypeScript
1 vote138 views1 answer
Typescript array of react elements
TypeScript
0 vote130 views1 answer
Coldfusion check if key exists and not empty
TypeScript
0 vote151 views1 answer
Which electromagnetic radiation is used for heating and night vision equipment
TypeScript
1 vote142 views1 answer
Adding paragraphs with foreach in angular docx.js
TypeScript