I have a user who shares a calendar with 2 other users (A&B). User A
can see the categories and colors of the appointments when they proxy
the calendar. User B only see's the appointments in black and white
and cannot see the categories when right clicking on the appointment.

All users are using the 8.0.2 HP1 client and backend (Linux).

I've run maintenance on the user B and event done a stuctural rebuild.
Not sure if there are any specific GWCheck options that might be