After archiving a user you have three options, either re-activating, deleting or anonymizing a users. If you decide to delete a user all the date is gone and can't be retrieved anymore if you want to do an end-of-year-report for example.
When you anonymize a user you will still be able to use the data for reports, except the data can no longer be traced back to a person because the user is made anonymous. So only the personal data is gone, the progress, score, likert-scale and quiz answers are still saved.
Note: you can only anonymise archived users.
Step 1. Make sure the user is archived, see this tutorial on how to archive a user. Click on User Management in the menu on the left.
Step 2. Search for the user in the search bar and click on his/her name to open the profile.
Step 3. Click on '...' on the right side of the user's profile picture.
Step 4. Click on 'Anonymize' in the menu that appears.
Congratulations, you now know how to Anonymize a user.