Fatal Error…

I have get_theme and improved plugin installation and neither of them will work… I try running them, and this comes up…

Fatal error: Cannot redeclare pclziputilpathreduction() (previously declared in /home/thebrack/public_html/wp-content/plugins/wordpress-automatic-upgrade/lib/pclzip.lib.php:5421) in /home/thebrack/public_html/wp-admin/includes/class-pclzip.php on line 5498

Would anyone have the slightest clue of what to do?