9 users all have a "SharedCalendar" ((a Shared Mailbox) that they put all events on so that all users can see. They don't use their personal calendars at all.
Within the last couple of weeks, when they open Outlook, they see the calendar twice. They can close one, but it re-loads next time they launch Outlook. Not a major problem, but apparently a major annoyance for a couple of key users.
I ran the "outlook.exe /resetnavpane" and the problem seemed to have resolved, but then the shared calendar disappears from their phones. As soon as I add it back to their phones then the duplicate re-appears in Outlook.
I feel like I'm missing something simple. Any suggestions?