Outlook 2016 offline address book not updating exchange 2016
Any changes you make while a connection to the server isn't available are synchronized automatically when a connection is available.
When the On Slow Connections Download Headers Only setting is selected, Outlook stops automatically downloading full items and also leaves attachments on the server.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.When you are using Cached Exchange Mode, an email message may remain in the Outbox for up to one minute until the next synchronization with the server that runs Exchange occurs.For example, you may use a laptop computer at your office and connect via a network cable to your corporate local area network (LAN).You have access to headers and full items, including attachments.Top of page Shared folders include Exchange Public Folders, Share Point folders, or another person's Exchange folders when you’re using Delegate Access.
By default, when Cached Exchange Mode is turned on, a local copy of shared folders is downloaded to your computer.
Use Cached Exchange Mode to work with items in your Microsoft Exchange Server mailbox even when your network connection is slow or unavailable.
You cannot use Cached Exchange Mode with a POP or IMAP account.
Later that day, you use a modem for dial-up access to your Exchange account.
Outlook recognizes your connection is slow and automatically optimizes for that connection by downloading only headers and not updating the Offline Address Book.
If Outlook is stuck in Offline mode, see Work offline in Outlook.