I have OpenSEF Installed

when I click username from the users online I get this error :

[code:1]Warning: main(/home/portsaid/public_html/alfystudio/templates/404.php) [function.main]: failed to open stream: No such file or directory in /home/portsaid/public_html/alfystudio/includes/sef.php on line 327

Fatal error: main() [function.require]: Failed opening required '/home/portsaid/public_html/alfystudio/templates/404.php' (include_path='/home/portsaid/public_html/alfystudio/administrator/components/com_sef:/home/portsaid/public_html/alfystudio/administrator/components/com_sef/includes:.:/usr/lib/php:/usr/local/lib/php') in /home/portsaid/public_html/alfystudio/includes/sef.php on line 327[/code:1]

any idea what that could be ?

Thank you

Here is a link to my forum :
www.alfystudio.com/component/option,com_fireboard/Itemid,46/

Looks fine here man, if you fix it send an update here so I don't go crazy looking for error

cheers