I have user1 who is supporting user2 and user3 that has been given Full Access permissions to both mailboxes. All mailboxes and archives show up in User1's Outlook.
User1 is using an E3 license and is running the 64bit CTR 2016 version of Office on Windows 10 Enterprise. Both Windows and Office has been fully updated.
User1's mailbox is fully synced and user2's mailbox looks completely normal. User3's mailbox within user1's Outlook is the issue.
User3's mailbox will NOT fully sync. I've checked the local and server data, it's 600MB vs 5.5Gb.
I've had to turn off cached exchange for the mailbox to show up fully, which works, but user1 is not happy with the slight delay with this option.
In cached exchange mode, I can manually touch a folder in User3's mailbox and choose update folder and the folder will update. But it will not update automatically.
I've tested this account on multiple machines with the same account and has run into the exact same issue.
I'm really looking for a setting that could be missed either in Office365 Admin or in Outlook that I have missed but this issue has been plaguing this user for some time.
Any help or suggestions would be greatly appreciated.