Drweb can get really annoying because of it’s resource usage even on a brand new Plesk server.
Run the following to remove drweb from your system:
rpm -qa | grep drweb | xargs rpm -e credit: http://box-admin.com/remove-dr-web-plesk-linux/
Update your mail server config
/usr/local/psa/admin/sbin/mchk --without-spam
Remove the cron entries
rm -rf /var/spool/cron/drweb rm -rf /etc/cron.daily/drweb-update
Disable monitoring by Watchdog
/usr/local/psa/admin/bin/modules/watchdog/wd --unmonit-service=drweb