Fatal error & now warning

This is what I get when I try and log onto my url – <ahref=”https://www.promosapient.com”&gt;

Warning: require_once(/home/content/86/7752386/html/wp-content/themes/arras/library/widgets.php) [function.require-once]: failed to open stream: No such file or directory in /home/content/86/7752386/html/wp-content/themes/arras/functions.php on line 55

Fatal error: require_once() [function.require]: Failed opening required ‘/home/content/86/7752386/html/wp-content/themes/arras/library/widgets.php’ (include_path=’.:/usr/local/php5/lib/php’) in /home/content/86/7752386/html/wp-content/themes/arras/functions.php on line 55

I know nothing about code and am using WordPress as such. This is ridiculous. Please help