Permission system provides an ability to set up a limited access for agents. Go to the Help Desk > Dictionaries > Permissions.The administrator is able to add a records on restriction access for each role of Magento store. As only Help Desk MX is installed (or updated to version 1.0.5+), there is only one record:

Role Has access to tickets of department Can remove tickets
All Roles All Departments Yes

It means that all the roles have an access to tickets from all the departments and any user is able to delete tickets.

Administrator can edit this record and add additional to setup correct permissions.

Let us imagine that we have three roles in our store: Administrators, Support, Sales. Let us set up Help Desk the way administrators would be able to access to every department and have an ability to delete the tickets, but Support and Sales would have a restricted access only to tickets from their departments without ability to delete them. To do this let us make a certain set up:

Role Has access to tickets of department Can remove tickets
Administrators All Departments Yes
Support Support No
Sales Sales No

Also take a note, if due to any reason a ticket went to the wrong department, in this case that department team members are able to redirect a ticket to another department. For example, even if Support Department team does not have access to tickets of Sales Department they are able to assign the ticket to the department Sales.

Help Desk MX