1. Login as admin and browse to Settings > Site administration > Plugins > Message outputs > Default message outputs.
2. Check that every combination is set to Permitted; that email is the default for everything, online and not online, except for "Personal messages between users". For personal messages the defaults should be popup: online and not online. email: not online.
3. Login as student1, browse to Settings > My profile settings > Messaging and check that the defaults are correct.
4. Save the changes.
5. Login as admin again and change the following default message outputs:
for Personal messages between users, disallow email, and force popup
for Subscribed forum posts, change the default when online from email to popup.
6. Login again as student1 and check that the forced settings for personal messages have taken effect.
7. Check that Subscribed forum posts has remained as email (as saved in step 4).
8. Login as student2, browse to Settings > My profile settings > Messaging and check that the updated defaults are shown.