I am trying to setup another shared calendar that will be used by two
people.  Each will be able to add appointments and have alerts set.

When I set up the new calendar (let's called it "Critical Calendar"), I
then go to add a new appointment for a specific date.

When I choose the alert setting (e.g. 1 day), and then click "Save and
Close", I get the following error message:

"The reminder for [Reminder Name] will not appear because the item is not
in your Calendar or Tasks folder.  Is this OK?  [Yes]  [No]"

I don't understand what it's saying.  The calendar I created is another
calendar underneath the main calendar.  Is this not possible the way I am
trying to do it?

I just need to have a second calendar that will allow for reminders and
alerts but it needs to be separate from the main calendar.