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From within your course go to the Settings block, if you are within an activity you may need to expand the Course administration sub-menu. From Course administration expand Users and then click on Enrolment methods.
Click the drop-down menu for Add method and chose Guest access
| By default when you add Guest access it is hidden, this means the enrolment method will not be applied until you unhide/activate it. |
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You may want to add an enrolment key for guests, this can be the same, or different to one for students.
From within your course, go to the Settings block, if you are within an activity you may need to expand the Course administration sub-menu. Under Course administration click on Edit settings.
This list contains a lot of course-wide settings but it also includes a group of options for Guest access, scroll down to find these:
To add a password for guests, set it in the Password field.
Click Save changes (at the bottom of the page)