title: HTML email, remove spacing between tr tags?
body: <p>I have tried adding cellspacing="0" cellpadding="0" . Does not fix the issue in email clients. </p>
  
  <p>Here is a image of the spacing in gmail:</p>
  
  <p><img src="https://i.stack.imgur.com/4Ie7O.png">
  </p>
  
  <p>HTML:</p>
  
  <pre><code>&lt;!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"&gt;
  &lt;html&gt;
  &lt;head&gt;
      &lt;title&gt;Openx Webinar&lt;/title&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;div style="margin:0;padding:0;font-family:Arial,Helvetica,sans-serif"&gt;
      &lt;table align="center" width="600" cellspacing="0" cellpadding="0" style="font-family:Arial,Helvetica,sans-serif" &gt;
          &lt;!-- Header --&gt;
          &lt;thead&gt;
              &lt;tr&gt;
                  &lt;td id="header" width="600" valign="top" align="left"&gt;&lt;img src="http://openx.dev.limusdesign.com/emails/webinar/images/header.png" alt="OpenX Webinar Series"/&gt;&lt;/td&gt;
              &lt;/tr&gt;
              &lt;tr&gt;
                  &lt;td id="banner" width="600" valign="top" align="left"&gt;&lt;img src="http://openx.dev.limusdesign.com/emails/webinar/images/banner.png" alt="Banner Image"&gt;&lt;/td&gt;
              &lt;/tr&gt;
              &lt;tr&gt;
                  &lt;td width="600" height="20" valign="top" align="left"&gt;&lt;/td&gt; 
              &lt;/tr&gt;   
          &lt;/thead&gt;
           &lt;/table&gt;
       &lt;/div&gt;
      &lt;/body&gt;
  
  &lt;html&gt;
  </code></pre>
  
  <p>Any advice on how I can fix this? NOTE: this is for HTML email. </p>
  
  <p>UPDATED HEADER CODE: </p>
  
  <pre><code>    &lt;!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"&gt;
  &lt;html&gt;
  &lt;head&gt;
      &lt;title&gt;Openx Webinar&lt;/title&gt;
      &lt;style type="text/css"&gt;
      div, p, a, li, td { -webkit-text-size-adjust:none; }
      &lt;/style&gt; 
  &lt;/head&gt;
  &lt;body&gt;
      &lt;div style="margin:0;padding:0;font-family:Arial,Helvetica,sans-serif"&gt;
      &lt;table align="center" width="600" cellspacing="0" cellpadding="0" style="font-family:Arial,Helvetica,sans-serif" &gt;
          &lt;!-- Header --&gt;
          &lt;thead&gt;
              &lt;tr&gt;
                  &lt;td id="header" width="600" valign="top" align="left"&gt;
                      &lt;img src="http://openx.dev.limusdesign.com/emails/webinar/images/header.png" alt="OpenX Webinar Series" height="65" style="display:block"&gt;
                  &lt;/td&gt;
              &lt;/tr&gt;
              &lt;tr&gt;
                  &lt;td id="banner" width="600" valign="top" align="left"&gt;
                      &lt;img src="http://openx.dev.limusdesign.com/emails/webinar/images/banner.png" alt="Banner Image" height="180" style="display:block"&gt;
                  &lt;/td&gt;
              &lt;/tr&gt;
              &lt;tr&gt;
                  &lt;td width="600" height="20" valign="top" align="left"&gt;&lt;/td&gt; 
              &lt;/tr&gt;   
          &lt;/thead&gt;
      &lt;/table&gt;
      &lt;/div&gt;
  &lt;/body&gt;
  &lt;/html&gt; 
  </code></pre>