I have also been having this problem since I started using the Events Manager plugin about a week ago, I just came here to post a new thread and saw this one!
Chrome gives me:
Error 6 (net::ERR_FILE_NOT_FOUND): The file or directory could not be found.
And turning on a debug log shows this error:
PHP Fatal error: Maximum execution time of 30 seconds exceeded in /hsphere/local/home/"username"/"site"/wp-includes/option.php on line 36
Is there a temp file created? (that I need to ensure I have enough permissions for?)