خطای session_start در نصب جوملا3

[آفرینا]

سلام
من می خوام یه بسته رو نصب کنم . در صفحه اول این خطا رو دارم.

Warning: session_start(): open(/tmp/sess_2a210ccc28c92ec2e816eff600c46323, O_RDWR) failed: No such file or directory (2) in /home/l/public_html/libraries/joomla/session/session.php on line 665

Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /home/l/public_html/libraries/joomla/session/session.php:665) in /home//public_html/libraries/joomla/session/session.php on line 665

Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /home/l/public_html/libraries/joomla/session/session.php:665) in /home//public_html/libraries/joomla/session/session.php on line 665

لطفا راهنمایی کنید باید چکار کنم برای رفع این خطا