We have what may be an odd use case for JSM - The 'customer' that submits a ticket will be an email group (tickets are submitted through an API call from an internal portal), but people in that email group will respond to the ticket. If the person responding does not already have a customer account, the comment on the ticket will not be posted.
How do I fix this? I tried going to System > incoming mail > mail handlers, and changing 'create users' from false to true, although this does not seem to have fixed the issue.
I would like responses from email addresses that do not have customer accounts to both post comments on tickets, and create the customer account as well, is this possible?