Salesforce has the feature that a user can choose to automatically fill the BCC field for all outgoing emails.
It is set via Settings > Email > My Email Settings > Would you like to automatically BCC emails to your return address?
For one of our users, this feature stopped working. The setting still had the value "Yes", but from a certain date, the BCC field was no longer filled automatically. For other users, it still works.
What is going on?