ruipedro it is only possible for users registered in AD to create a ticket and prevent the creation of tickets on the home page
This appears to be two separate unrelated questions.
ruipedro it is only possible for users registered in AD to create a ticket
Yes. You would have to create or sync your users from AD to osTicket. Then they would be able to email the ticket system and/or go to the UI and create a ticket.
ruipedro prevent the creation of tickets on the home page
I don't think so. I think that if a user has an account they can log into and create a ticket. Although the Registration options seem to indicate differently. (see the last in the table)