The csv import never worked, never imported anything. The only method that imports anything at all is bulk. There is only one field – email address. List tested with is 4200 entries.
Bulk import does not detect duplicates unless imported into the same list. To further test, I used the bulk import and imported a list that had already been sent, into a new list. (The only way to know which were already sent in the old list was to change their status to unsubscribed. Status should make no difference when importing. If the email is in the list at all, there needs to be at least the question, the choice of what to do, when a duplicate is added.). The new list imported without finding any duplicates whatsoever, but only by bulk import.
I then tried to import the same entries into the same test list and it would not import any new entries with csv or bulk, into the this list. They were already in the list. This is the needed response, but across all lists.
I then made yet another new list and tried to import the same list by csv. It, again, would import no files using the csv method. I used bulk import again and it re-imported the same list without finding any duplicates. It made a second list, same as the first, re-duplicating all entries, triplicating some entries that had already been sent, and whose status had been set to unsubscribe, in order to tell they had been sent, since the plug provides no way to track who has been sent what and/or when.
This duplication will get you a lot of heat from recipients, lose potential subscribers, and can cause problems with CAN-SPAM. It has brought this project to a halt altogether!
