we have:-
$string['confignavshowallcourses'] = 'If enabled users will see courses they are enrolled in both within the My Courses branch and the course structure. When disabled users with enrolments will only see the My Courses branch of the navigaiton. The number of course shown would still be limited by "Course limit(navcourselimit)" setting when user is either not logged in or not enrolled in any course.';

'navigaition' is a typo