Warning when activate the plugin

Warning: is_dir() [function.is-dir]: open_basedir restriction in effect. File(..) is not within the allowed path(s): (/var/www/vhosts/khaibeatsounds.com/site1/:/tmp/) in /var/www/vhosts/khaibeatsounds.com/site1/wp-content/plugins/pricing-table/libs/class.plugin.php on line 54

Warning: Cannot modify header information – headers already sent by (output started at /var/www/vhosts/khaibeatsounds.com/site1/wp-content/plugins/pricing-table/libs/class.plugin.php:54) in /var/www/vhosts/khaibeatsounds.com/site1/wp-content/plugins/easy-digital-downloads/includes/libraries/class-wp-session.php on line 123

This is the message shows me the header of my home.

I need heeeelp!!

http://wordpress.org/extend/plugins/pricing-table/