ost file) on the user's computer, together with an Offline Address Book (OAB).Ĭached Exchange Mode's purpose is to provide a seamless online and offline Outlook experience. When an Exchange account in Outlook is configured to use Cached Exchange Mode, Outlook works from a local copy of the user's Exchange mailbox that is stored in an offline data file (. Outlook for Mac desktop versions (including 2016) support only Cached Exchange Mode.Ĭached Exchange Mode is the default and recommended configuration for most scenarios except those mentioned under When to use Online Mode.

See Configure Exchange Online with Outlook or Windows Mail.Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread. If the response is helpful, please click ' Accept Answer' and upvote it. If your issue has any update, please feel free to post back. If the issue still exists, it may also be caused by corrupted Outlook client, please try to repair your Outlook to check. If the issue could be reproduced in safe mode, considering corrupted outlook profile may cause it, it's suggested to create a new Outlook profile and readd your account for testing(Control Panel>Mail>show profiles>Add>Readd your account). But after updating office, the problem comes back again.īased on my research and tests on my Outlook 2016 (.1000), the option wouldn't be changed when I close and restart Outlook client, considering it could work well after you reinstall office, the issue may be related to your client itself, so what's the version of your Outlook 2016(File>Office account>About Outlook)? Please first ensure that you have installed the latest update of Outlook client, and have you performed any other operations except updating office before it(such as install any programs or add-ins)?įirst of all, in order to avoid the interference of add-ins, we could try to test on safe mode to check if the issue has any difference there(restart your Outlook in safe mode: windows + r, type 'Outlook.exe /safe', click enter> modify the option settings>close the Outlook>restart Outlook in safe mode again to check if the option would be changed). Hi I reinstalled my office 2016, it was working well.

Outlook 2016 not saving settings