It depends on how that user is licensed....are they Staff or a Client? If Staff are they a full license or a casual user license? There are restrictions on who can access certain areas of the console depending on their license and what they will be doing.
I tested with a user - unchecked the box, saved, logged in; the user could still get to Remedyforce Console. Not sure if there any permissions tied to that field. Useful for reporting though.
The user i want to add is Staff user that can Add, edit, delete incident. Also what is the difference between "full license or a casual user license? "
Did you check that box "Service Desk staff"? If not you can add it to the page layout of "User". Click edit layout upper right of the user page.
Remedyforce casual users will have the same functionality as Remedyforce standard users (Remedyforce Service Desk Staff or licensed user), but their average login time and number of records updated may not exceed 40% of the average login time and number of records updated by standard users in the same Org.
If a user whose "Service Desk Staff" checkbox is unchecked but has necessary permission needed to access Console, can use Console to create/edit/delete Incident etc.
However, other users cannot assign a record to such a User because the Staff lookup will show only such users for whom the "Service Desk Staff" is checked.
Hence it is better to keep all Console users "Service Desk Staff" as checked.