title: SmtpClient .send() error: "message rejected as spam by content filtering"
body: <p>Here is the code i wrote to send email,</p>
  
  <pre><code>MailMessage m = new MailMessage();
  SmtpClient sc = new SmtpClient();
  sc.UseDefaultCredentials = false;
  
  try
  {
      m.From = new MailAddress(Sender);
      m.To.Add(new MailAddress(Receiver));
      m.Subject = Subject;
      m.IsBodyHtml = true;
      m.Body = Body;
  
      sc.Send(m);
  }
  catch (Exception ex) { _Exceptions.ManageExceptions(ex); }
  </code></pre>
  
  <p>And the config file settings:</p>
  
  <pre><code>&lt;system.net&gt;
      &lt;mailSettings&gt;
          &lt;smtp deliveryMethod="Network" from="xxx@xxx.com"&gt;
              &lt;network host="192.168.0.170" userName="setsdom01\user1" password="xxx" port="25" /&gt;
          &lt;/smtp&gt;
      &lt;/mailSettings&gt;
  &lt;/system.net&gt;
  </code></pre>
  
  <p>It executes when i run it from my machine, i try on different PC and it is giving me the following message: ...<strong>message rejected as spam by content filtering</strong>..</p>
  
  <p>What could be the problem?</p>