How to remove this cronjob in ubuntu

Question

I'm running a webserver with PLESK and installed an extension 'kernel care' which I later on deleted. However, it installed a cronjob which sends me a mail every 4 hours:

Cron <root@server> /usr/bin/kcarectl --auto-update
Unknown Kernel (Ubuntu 3.13.0-042stab123.9)

I ssh into the server and run crontab -l as root but don't see the specific cronjob. However, in /etc/cron.d there is a file kcare-cron and if I cat this file it shows

16 */4  * * * root /usr/bin/kcarectl --auto-update

So thats the one I want to delete. Can I just delete the file kcare-cron?

Answer 1

1- Open terminal & type

sudo crontab -e

Now either remove cron command or marked '#' at start of command. Now save file (ctrl + O, & ctrl +X) & exit.

2- Do second option

sudo crontab -r

Note: This will remove all cron job.