Outlook 2016 cached mode not updating shared mailbox
It does not apply the sync settings to the new Groups feature as Groups are cached in in a separate data file (account-name.nst).
Users who need to limit the amount of data cached locally can set up filters on each folder.
To do this, right click on the folder and choose Properties, Synchronization tab. You'll need to repeat this on each folder where you want to limit what syncs.
Because only Public Folder Favorites sync, removing folders not needed offline from the Public Folder Favorites list will help to reduce the size of the cache.
In Outlook 2016, the sync slider also limits the age of mail sync in shared mailboxes that are cached.
To check the sync settings, open File, Account Settings dialog and double click on the email account.
In Outlook 2016, shared mailboxes do not (currently) have the link (or active View on Server button) to view more messages on the server.
For Outlook 2013, Exchange accounts can sync as little as 1 month, while Outlook 2016 can sync as little as 3 days of messages.
The sync settings do not apply to the following Outlook items. When Exchange server users have shared or delegate folders, shared mailboxes, and public folders in a profile, Outlook 2013 caches the contents of these folders in the *file, however, the sync setting does not apply to these folders, and all contents of these folders are stored in the local cache file.
Outlook 2016 applies the sync setting to shared or delegate folders and mailboxes, and public folders that are cached.
By default, when Cached Exchange Mode is turned on, a local copy of shared folders is downloaded to your computer.
To change whether shared folders or Public Folders are downloaded when Cached Exchange Mode is turned on, do the following: Cached Exchange Mode enables a better experience when you use an Exchange account.