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How to send an SMS from the Event page
Go to the Event page
Select My Apps in the top menu
Select Events
Select the Event you are interested in
You will arrive on the Event page
Select Message Guests in the Event Actions panel
The Message Guests popup appears. It only lists the guests that have a valid mobile number saved in one of the designated fields
Select the guests whom you would like to message
Type the message in the box
Choose whether you want to send the message Now or scheduled for Later
If you select Later, you can enter the Date and Time that you want the message to be sent
Press Send