Windows Calendar stops working - Reminders do not pop up
 

I am using Windows Calendar with Vista Home Premium.

Every month or so my Appointment reminders do not work.

When I realize that this is happening, I open Windows Calendar and click on
an Appointment to open it. Then, I get a pop-up window with all the reminders
that should have fired earlier.

I am just about ready to look for another calendar product.

What is happening here?

Is the calendar app not being loaded for some reason?

How can I check to see if it is running when I start up my laptop.

(I am not sure if this matters, but I do not use MS Outlook at all. I think
there is a calendar in Outlook. I am using Windows Calendar from the Start
menu.)

I would appreciate some help. I cannot afford to miss an appointment
reminder.

Is Windows Calendar unreliable? It is looking that way to me right now.