On occasion I get the following string of errors when I attempt to delete an email after opening it to the full view. Can anyone assist?

Thanks in advance

Warning: return_module_language(modules/i/language/en_us.lang.php): failed to open stream: No such file or directory in /var/www/html/crm/include/utils.php on line 839

Warning: return_module_language(): Failed opening 'modules/i/language/en_us.lang.php' for inclusion (include_path='.:/usr/share/pear') in /var/www/html/crm/include/utils.php on line 839

Warning: Cannot modify header information - headers already sent by (output started at /var/www/html/crm/include/utils.php:839) in /var/www/html/crm/include/utils.php on line 1943

Warning: Cannot modify header information - headers already sent by (output started at /var/www/html/crm/include/utils.php:839) in /var/www/html/crm/index.php on line 495

Warning: Cannot modify header information - headers already sent by (output started at /var/www/html/crm/include/utils.php:839) in /var/www/html/crm/index.php on line 499

Warning: Cannot modify header information - headers already sent by (output started at /var/www/html/crm/include/utils.php:839) in /var/www/html/crm/index.php on line 503

Warning: load_menu(modules/i/Menu.php): failed to open stream: No such file or directory in /var/www/html/crm/include/utils.php on line 274

Fatal error: load_menu(): Failed opening required 'modules/i/Menu.php' (include_path='.:/usr/share/pear') in /var/www/html/crm/include/utils.php on line 274