We can add some security roles to multiple users in single operation by selecting users in view, clicking "Manage Roles", selecting roles and clicking "OK". But sometimes, the error message below appears : "An error has occurred. The selected action was not completed for one or more records." This occurs if there's at least one user which has already been applied the role in the request.
But only with this ambiguous message, we cannot know - which users are applied roles correctly - which users aren't applied - what roles are already applied the user(s) And to figure out them, we have to open user record one by one and check if the user already have the role. This takes too much time when we want to apply roles for many users.
Please consider improving this behavior like this : - If there's some users that already have the roles selected, just do nothing for such roles and appliy roles that the user don't have yet. or - If the above is difficult, please show the list of users which haven't been applied.