Delete Blog Error

Tried to delete a blog but received below message.

Warning: reset() [function.reset]: Passed variable is not an array or object in /home/s28632/public_html/wp-admin/includes/mu.php on line 50

Warning: Cannot modify header information - headers already sent by (output started at /home/s28632/public_html/wp-admin/includes/mu.php:50) in /home/s28632/public_html/wp-includes/pluggable.php on line 856

Your assistance please. Thank you.