I have 550 or so users on my Moodle across the world. I have found recently that a few (about 5 -10) of these users do not appear in the gradebook. They DO appear in logs as having taken assessments and I can find the results in the database. I have also added a table to the profile page so each user can see all their assessment passes here and Moodle displays this correctly for these users. It is only the gradebook where they do not appear.
At present I can see no reason for this at all. I see a few other people have had similar problems and I'm hoping someone somewhere has found a solution to this.
If you can help please let me know. I will of course post a solution if I find one myself.