I have setup Nextcloud (Cloud storage sharing) on a hosted platform, I am trying to setup SMTP on the service so that it will send out notification emails. I have it all setup correctly and I can test it and it will send to my Domain email address. When I setup a new user that has an email address outside our company, Nextcloud will send the message it gets routed to our barracuda system but it blocks it as Invalid Domain.
Any ideas?