Simple Ethernet Shield Program - Acts different

hi all,

so i'm trying use ethernet shield send simple email via smtp using telnet.

the problem shield unpredictable. code below worked once , not connect server. used return 0 @ client.connect("smtpcorp.com", 2525); stays stuck @ function. 0 not valid return value according http://arduino.cc/en/reference/clientconnect.

here's code:

code: [select]

// email via telnet

#include <spi.h>
#include <ethernet.h>

byte mac[] = {  // mac adress
  0xde, 0xad, 0xbe, 0xee, 0xee, 0xee };
ipaddress ip(192,168,1,66); // ip\

//ip address of server 207.58.147.66
ipaddress server(207,58,147,66);

//initialize client libaray
ethernetclient client;

void setup(){
  // start ethernet connection mac , ip
  ethernet.begin(mac, ip);
  serial.begin(9600);

  delay(1000);
  serial.println("connecting...");

  // if connection, report via serial:
  int connectstat = client.connect("smtpcorp.com", 2525);
  serial.println(connectstat);
  if (connectstat) {
    serial.println("connected");
  }
  else {
    // if didn't connection server:
    serial.println("connection failed");
  }
}

void loop(){

  if (client.available()) { // read see if there read
    char c = client.read();
    serial.print(c);
  }
   if (client.connected()) {
      client.print("ehlo");
    }
      if (client.available()) { // read see if there read
    char c = client.read();
    serial.print(c);
  }
    while(true);// stay here , nothing

}


void senddata(){
}


can explain going on , how can connect reliably?

the valid return value successful connection using domain name 1. 0 (unable connect server) or negative (unable resolve domain name) return value failed connection.

code: [select]

  if (connectstat == 1) {
    serial.println("connected");
  }
  else if (connectstat == 0) {
    // if didn't connection server:
    serial.println("connection failed");
  }
  else {
    // if didn't resolution on domain:
    serial.println("dns failed");
  }



edit: had them change client.connect reference page show dns fails (-1 -5), left out 0 return, unable connect server.

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