Is there a way to prevent a new contact from being created if the email already exists with another contact?
When a new contact is added, if the email already exists, I would like an error saying that contact can not be created because email already exists.
UPDATE: So to add further details about my question...
OTHER AREAS LIKE EVENTS One of the comments below stated "if an existing contact tries to use a registration form do you allow or disallow that record to be updated?". So I am not sure exactly how CiviCRM works, but in this case above, I would want the existing contact information to be used, and would not want a new contact created. So I do not want to prevent updating of existing records, I would just want to prevent a duplicate contact with a duplicate email as being created. This particular scenario is probably something I will come across in the near future as we move forward with CiviCRM implementation, but is currently not an issue I have to deal with (yet).
IMPORTING I did notice that when I import contacts, I can choose DeDupe rule of EMAIL (RESERVED), and this will correctly skip importing any contact if the email already exists. So this is solved and is not an issue.
MANUAL ADDING CONTACT When manually adding a contact though, I am unable to prevent a user from adding a new contact with a duplicate email. I see there is a button that says CHECK FOR MATCHING CONTACT(S) ... If the EMAIL (RESERVED) rule is set to Unsupervised, then click this button does not find a match (even when one exists). If I change the rule to Supervised, then clicking the button will find a match. However this is still not the functionality that I want, as it still does not prevent the user from adding the contact if they either forget to click the CHECK FOR MATCHING CONTACT(S) button or if they choose to ignore the message that it found a match... This is
So what I want to be able to do, specifically for Manually Adding Contacts, is that when the SAVE button is clicked it will just give an error message saying "Contact Email already exists. Can not add new contact", or "Contact Email already exists. Would you like to add it anyways?"
I looked at CiviRules but did not see how I can implement this using that module.