Typically, there are not true duplicates, but instead records marked as Do not Register.

Notice the Registration Column, does it contain a notation of "Do not register"?

A few scenarios in which the Do not register notation will be present:
  • The registrant's participant name is different than the billing name used
  • One person registers a different user
  • A person registered on behalf of an organization
There is not a setting to prevent the Do not register notation from occurring.

To filter on only registered participants:
Starting point: The Raiser's Edge>Records>Events>Open Event>Participant tab
  1. Click the filters button
  2. Select Registered from the Registration dropdown
  3. Click OK
For more information review our Knowledgebase Event registrant marked as Do Not Register.