title: "Failure sending Mail" error on program
body: <p>my friend gave me a program which runs in his laptop, he coded with system.webmail and C#, that program can send the email in his machine, but when i run and send it out in my machine, the email didn't send and get "Failure Sending Mail", but in his computer, he can send with his internet. But I am still getting error, even i can't ping to SMTP server or telnet. What will be issue, does my ISP ban the port, or ISP firewall ban the port? </p>
  
  <p>I use port 25 and also 587 too. but it doesn't do any different at all.</p>