title: block specific type of email address in php via regex
body: <p>I use the following regex pattern for validating the email address that works fine. </p>
  
  <pre><code>/^[^\@]+@.*\.[a-z]{2,6}$/i
  </code></pre>
  
  <p>But the problem is I want to generate error if email like <code>abc.abc@yahoo.com</code> are enter. Actually all those emails are invalid which have characters same as before &amp; after <code>**.**</code> like <code>xyz.xyz@gmail.com</code> invalid, <code>qwe.qwe@hotmail.com</code> invalid</p>