Smart PHP Calendar has a great reminder system. You can define multiple reminder templates for each calendar. reminders To set default calendar reminders click icon on the right side of the calendar. Then click Reminders Tab.

Reminder Message Templates

You can set each calendar's email, popup and sms message templates by using Reminder Messages. reminders messages

Email Reminders

To get email reminders Cron Jobs must be set. CRON Jobs are used to trigger certain commands periodically.
Use the following command for email reminders in your server management CRON panel.
                //email reminders
                * * * * * curl
                //sms reminders
                * * * * * curl

Test Email Reminders

To test email reminders manually open page with your browser. You will see emails and event information if you have an event on page open time.

* Please make your email server configurations in config.php file to get email reminders properly.

Popup Reminders

You do not need to do any configuration for Popup reminders. Just set popup reminders in your event details and they will be triggered.

SMS Reminders

You can set SMS reminders in your events but to get SMS reminders you need to integrate your SMS service to our API.
We use Twilio as our SMS service provider. To get SMS reminders please just signup for twilio and copy your ACCOUNT SID and AUTH TOKEN to config.php file. For more information please visit:
If you want to integrate your own SMS API please see "system/apps/calendar/models/Reminder.php" file sendSMS method.