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Results tagged with Search options user 401

Use this tag for questions about preventing, finding, and merging duplicate contacts. This includes composing duplicate matching rules, using the dedupe system, strategies for preventing false matches, and merging a pair of contacts.

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It seems your event registration profile form has no email field or last name field for duplicates checking, refer to this related post How to register for event without an email address? Also refer …
answered Feb 6 '16 by Kboy