Hey Pritha!
The information provided by Cvent below is a great way to handle it, however... you should think of the Cvent system as a CRM. When an attendee attends any event, it logs their email along with all their registration information into their contact record. Each time they join another event, it updates their information based on that. If someone wants their email to change completely, the best way is to update their contact record. (Top right, change views to go to contacts). This will update their email for ALL uses of their email so, if they registered for multiple events, then it will change it across all events.
One other thing to note, if you have a lot of questions during your registration process and you use substitute registrant... it will NOT keep the answers to their questions and they will have go back in and update their registration to include the answers to all of those questions.
Thanks!
Mike
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Michael Rummage
Senior Director, Events & Special Projects At Quility Insurance
QuilityUnited States
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