Answers.Body: <p>Assuming you're allowing registrations from users who aren't logged in, you might check the duplicate checking rule that you're using for the event and make sure that you're collecting enough information for the rule to match.  </p>
  
  <p>For example, if you don't require an email address, and your duplicate matching rule matches on email address, you'll create duplicate contacts, each with their own registration.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2015-05-27T16:07:24.590Z
Answers.Text: Its not duplicate checking thats the problem. the contact is not duplicated, but the one contact gets duplicate registrations for the event. Ghost's suggestion above has fixed this.
Answers.UserDisplayName: Dave Florence
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2015-05-27T15:53:43.093Z
Answers.LastActivityDate: 2015-05-27T15:53:43.093Z
Answers.UserDisplayName: Andie Hunt
Answers.Body: <p>Check if 'Same email address?' checkbox is ticked in Manage Event >> Configure Event >> Online Registration.</p>
  
  <p>If this checkbox is enabled, CiviCRM will allow a user to register multiple times using the same email address.</p>
  
  <p>Untick 'Same email address?' checkbox to prevent people from registering for the same event more than once.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2015-05-27T15:46:51.250Z
Answers.LastActivityDate: 2015-05-27T15:46:51.250Z
Answers.UserDisplayName: Ghost
Body: <p>We are advertising a free event which people can sign up for online.</p>
  
  <p>People are registering themselves more than once for the event so we are getting duplicate registrations.</p>
  
  <p>If we use the back end to try to add a person to an event that they are already registered for, the system does not allow it. - That's fine.</p>
  
  <p>We would like to make it so people cannot register for an event they are already registered for .</p>
  
  <p>Why does the online registration allow this to happen ?</p>
  
Tags: <civievent>
Title: how to prevent people enrolling for an event twice
ThreadText: # how to prevent people enrolling for an event twice
  
  (Asked by: username_0 on 2015-05-27)
  
  We are advertising a free event which people can sign up for online.
  
  People are registering themselves more than once for the event so we are getting duplicate registrations.
  
  If we use the back end to try to add a person to an event that they are already registered for, the system does not allow it. - That's fine.
  
  We would like to make it so people cannot register for an event they are already registered for .
  
  Why does the online registration allow this to happen ?
  
  **Tags:** civievent
  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_2 on 2015-05-27. Score: 8 | Accepted answer
  
  Check if 'Same email address?' checkbox is ticked in Manage Event >> Configure Event >> Online Registration.
  
  If this checkbox is enabled, CiviCRM will allow a user to register multiple times using the same email address.
  
  Untick 'Same email address?' checkbox to prevent people from registering for the same event more than once.
  
  
  ---
  
  ### Answer by username_1 on 2015-05-27. Score: 3
  
  Assuming you're allowing registrations from users who aren't logged in, you might check the duplicate checking rule that you're using for the event and make sure that you're collecting enough information for the rule to match.
  
  For example, if you don't require an email address, and your duplicate matching rule matches on email address, you'll create duplicate contacts, each with their own registration.
  
  > **Comments:**
  > **username_0**: Its not duplicate checking thats the problem. the contact is not duplicated, but the one contact gets duplicate registrations for the event. username_2's suggestion above has fixed this.  
  
  ---
  
  