Allowing access to a limited group of users

[Adam Fenyves]

Dear Community,

I am setting up a Service Desk project, and would like to enable ticket opening only via email (simply by not communicating the portal). I would like to enable any of our customers report issues, but noone else. (so it would mean any email  from their domains should open a new ticket, while others, such as gmail.com should not). Is there a way to do this without manually registering each user? I couldn't find such option. Thank you!

[Alexey Matveev]

You can change customer permissions in two places:

And here:

[Adam Fenyves]

These two I know, but as I stated these are not the ones I am looking for. This way I either have to:

- allow anyone send emails that will result in a new ticket

or

- administer every email address/user individually.