Error on installation

I have installed the pluggin how ever when i go to activate the plugin i get the following error message

Warning: exec() has been disabled for security reasons in /home/pegidauk/public_html/wp/wp-content/plugins/awstats-report-viewer/Modules/Report/Model/AWStats.class.php on line 100

Could some one help me with it plesae.

https://ww.wp.xz.cn/plugins/awstats-report-viewer/