Updating address book outlook
The best you can do with Office 365, is to wait until the next day after 5am, and then either restart outlook or force the OAB download using the below method.Hardly ideal, but until Microsoft add this functionality this is the only option. https://office365.uservoice.com/forums/264636-general/suggestions/14919246-please-allow-admins-to-force-update-offline-addres To download the latest copy of the OAB manually, follow these steps: 1.You may see a status window indicating the download's progress, it will automatically disappear when completed. Re-open Outlook and log in; the Global Address List should now contain the most recent information.When a new email account is created in Exchange it will not normally appear in the address book of others until the following day.
Check back after another 24 hours to see whether the OAB is updated.’ Note that you can see a schedule by running the following command: $schedule = Get-Offline Address Book “Default Offline Address Book” | Select-Object schedule $schedule.If you are not seeing correct contact information in the GAL for someone that has a valid email address (i.e.someone who just received a UAEX Exchange account use the steps below to synchronize your computer's locally cached version of the GAL. The most recent version of the Global Address List will be downloaded.Schedule Sun.-Sun. Mon.-Mon. Tue.-Tue. Wed.-Wed. Thu.-Thu. Fri.-Fri. Sat.-Sat. However, as per https://blogs.technet.microsoft.com/exchange/2013/01/14/managing-oab-in-exchange-server-2013/ later versions of Exchange don’t use this setting, you should use get-mailboxserver [servername] | fl *oab* however this command is not available in Exchange Online.I assume therefore that this 5am schedule is the setting that is used either way, but frankly can’t be sure.
While in Offline mode you will have to enter the full email address for any recipient that isn't saved in your contacts list.