Errors in admin part of my site.

I'm receiving the following errors on the admin portion of my site. Is there an update that I can do?

Thanks!

Warning: session_start() [function.session-start]: open(/home/content/w/i/l/williemcneil/html/sessions/sess_2b42bd6303b7c833c98e61f32ecea13b, O_RDWR) failed: No such file or directory (2) in /home/content/00/13585700/html/web/admin/config/ProjectConfig.5.3.php on line 0

Warning: session_start() [function.session-start]: Cannot send session cookie - headers already sent by (output started at /home/content/00/13585700/html/web/admin/config/ProjectConfig.5.3.php:0) in /home/content/00/13585700/html/web/admin/config/ProjectConfig.5.3.php on line 0

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/content/00/13585700/html/web/admin/config/ProjectConfig.5.3.php:0) in /home/content/00/13585700/html/web/admin/config/ProjectConfig.5.3.php on line