Make sure you configured SysAid to send outgoing mail properly, you can see the settings in our Online Aid:
The end users will receive emails based on the settings you can find under helpdesk settings , General tab
Just one thing, in order for an end users to get automatic emails from SysAid they need to be registered under the end users.
Anyone can send an email to your helpdesk account and it will turn into a ticket - only end users you manage will get automatic notifications
Good Luck !