# Locked completion options

If at least one person has completed an activity, completion options are 'locked'. This is because changing these options may result in unexpected behaviour.

## Potential confusion

If somebody has ticked an activity as manually completed, and you then set it to automatic completion, the activity will become unticked - very confusing for the student who had already ticked it!

It is best not to unlock options unless you are sure it won't cause problems - for example, if you know that students don't have access to the course yet, so it will only be staff who have marked the activity completed when testing.

## What happens when you unlock

Once you unlock options and then click 'Save changes', all completion information for the activity will be deleted and, if possible, regenerated according to the new settings.

- If the new completion option is manual, everyone will be set to 'not completed' regardless of any previous setting.
- If it is automatic then, depending on the options chosen, the system may or may not be able to construct a correct current value for everyone.
  - The 'viewed' requirement will not work - even if a student has viewed the activity before, it will not be marked completed until they view it again.
  - Most other options will be recalculated successfully.

If you change completion options while a student is logged in, they may not see the changes for some minutes.