turboSMTP will not consider subscriptions made with free email providers
like Gmail, Hotmail, Yahoo! or the likes.
The reason is simple: such free accounts are very often used by spammers to deliver scam messages and don't allow to configure DKIM and SPF
to ensure the highest delivery rate. Since we have to protect the efficacy of our servers (and, consequently provide the best service for our clients) we are going to refuse all registration proposals coming from free email accounts
To get accepted by turboSMTP it's thus necessary to have an account related to an owned and real domain
(such as email@example.com