I have a single user who does not appear in the GAL. I have performed the following:
Deleted and recreated the account.
Deleted and recreated the GAL and offline address books.
Replicated the AD.
Reapplied the recipient policies.
Restarted the services.
Restarted the servers.
Banged my head repeatedly against the wall.
Easily upload multiple users’ photos to Office 365. Manage them with an intuitive GUI and use handy built-in cropping and resizing options. Link photos with users based on Azure AD attributes. Free tool!