title: Can not add new site - WPMU
body: <p>I installed WPMU on hostgator, everything is fine except I can not add new site in wp-admin/network/sites.php</p>
  
  <p>I installed the fresh WP4.2.2 with default WP theme, no plugins activated.</p>
  
  <p>I faced this errors</p>
  
  <blockquote>
    <p>Warning: preg_match() expects parameter 2 to be string, object given
    in /home1/xxx/public_html/wp-includes/formatting.php on line 3435</p>
    
    <p>Warning: preg_match() expects parameter 2 to be string, object given
    in /home1/xxx/public_html/wp-includes/formatting.php on line 3424</p>
    
    <p>Warning: preg_match() expects parameter 2 to be string, object given
    in /home1/xxx/public_html/wp-includes/formatting.php on line 3435</p>
    
    <p>Warning: strip_tags() expects parameter 1 to be string, object given
    in /home1/xxx/public_html/wp-includes/formatting.php on line 3407</p>
    
    <p>Warning: strip_tags() expects parameter 1 to be string, object given
    in /home1/xxx/public_html/wp-includes/formatting.php on line 3407</p>
    
    <p>Catchable fatal error: Object of class WP_Error could not be converted
    to string in /home1/xxx/public_html/wp-includes/kses.php on line 1038</p>
  </blockquote>
  
  <p>The screen is dead at this.</p>
  
  <p>I contacted with hostgator support staff but they can't solve the problem.</p>
  
  <p>Can someone give me a suggestion please?</p>
  
  <p>I really need to get the site works properly.</p>
  
  <p>Thanks,</p>