[otrs] no mail when a new ticket is created

Hello, I've made some new queues (for example 'hardware problems') and new groups ('intern users' and 'extern users') When I connect the queue 'hardware problems' to the group 'intern users' I don't get an emailnotification when a new ticket is created. If the ticketstate is changed, ticket is moved,.. I do get an emailnotification. If I connect the queue 'hardware problems' to the standardgroup 'users' I do get an emailnotification when a new ticket is created... What have I done wrong, missing a parameter somewhere?? Greetings, Rene Koning