Crontab -e You (oracle) are not allowed to use this program (crontab)

$ crontab -e
You (oracle) are not allowed to use this program (crontab)
See crontab(1) for more information

# The following files control crontab usage

/etc/cron.allow
/etc/cron.deny

# Go to the root user and add oracle user to the following file:

echo oracle > /etc/cron.allow

# Or delete oracle from /etc/cron.deny file. 🙂