I want to reboot my Wordpress server once per day, automatically through a CRON job.  I've tried multiple ways to get this done, based on various google searches and suggestions.  But, it never seems to work.

Can you suggest an easy solution for this?

I tried creating:

/etc/cron.daily/zz-reboot

AS:

#!/bin/sh
shutdown -r now

Setting it executable:
chmod a+x /etc/cron.daily/zz-reboot

The "zz" prefix is supposed force it to run last out of all the other scripts in that directory.  But it doesn't execute.

I tried creating a new CRON job in WebMin that does nothing but 

reboot

As suggested elsewhere, but it doesn't do anything.