What happens if I import duplicate email addresses?
If the file you're importing contains the same email address more than once, the software will detect it and only import one record for the email address.
When this happens an 'import report' is generated after the file has been uploaded (which remains available for 10 days). Under the heading "Duplicates" (see below) you'll see one or more examples of the duplicate emails and a Download all button to export them as a CSV file.
You can of course have the same email address in two separate lists in your account. If you send a single campaign to more than one list, and the same address is on multiple lists, those duplicates will be identified so each email address only gets one email.