Error message

• Warning: date_timezone_set() expects parameter 1 to be DateTime, boolean given in format_date() (line 2014 of /var/www/vhosts/oasischorale.com/websites/www/httpdocs/includes/common.inc).
• Warning: date_format() expects parameter 1 to be DateTime, boolean given in format_date() (line 2024 of /var/www/vhosts/oasischorale.com/websites/www/httpdocs/includes/common.inc).
• Warning: date_timezone_set() expects parameter 1 to be DateTime, boolean given in format_date() (line 2014 of /var/www/vhosts/oasischorale.com/websites/www/httpdocs/includes/common.inc).
• Warning: date_format() expects parameter 1 to be DateTime, boolean given in format_date() (line 2024 of /var/www/vhosts/oasischorale.com/websites/www/httpdocs/includes/common.inc).
• Warning: mktime() expects parameter 4 to be long, string given in wp_blog_views_post_render() (line 41 of /var/www/vhosts/oasischorale.com/websites/www/httpdocs/sites/all/modules/wp_blog/wp_blog.views.inc).