Warning: require_once(header1.shtml): failed to open stream: No such file or directory in /home/js1/public_html/default.php3 on line 31

Fatal error: require_once(): Failed opening required 'header1.shtml' (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/js1/public_html/default.php3 on line 31