[Moodle] Problem enrolment keys

[Graetz, Kimberley K]

Hi All,
We have been using moodle for about a year (version 1.8+). However, we
are having problems with the enrolment keys. We have placed an enrolment
key on every course. 
We have the following boxes filled in like this:

Enrolment plugin --> Site default
Course enrolment --> yes
Enrolment duration --> unlimited
Availability --> this course is available to students Enrolment -->
filled with the code

However, the enrolment keys are not working and every student is able to
access every course. I thought that I could be a permission problem with
students. But I have put these back to default mode with no change. Is
there anything that I am leaving out or doing something wrong? Please
help!!!

Kim Graetz
Wangaratta High School
e-Learning (Maths and Science)

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