Hi @Robyn,
Can you run the following query in your MySQL database?
SELECT s.symbolic, s.assoc_type, s.assoc_id, s.user_id FROM signoffs s LEFT JOIN users u ON (s.user_id = u.user_id) WHERE s.user_id IS NOT NULL AND u.user_id IS NULL AND s.user_id <> 0;
If this results in any rows, those rows will need to be corrected – they’re cases where assignments are made to users who don’t exist. I suspect that’ll include your situation.
It’s likely that upgrading to a more recent release of OJS would have prevented this from happening, but once there’s a data error in place, you’ll need to correct it manually either way.
Regards,
Alec Smecher
Public Knowledge Project Team