By default, changes made in Dynamics 365 are synchronized with Microsoft Dynamics 365 for Outlook every 15 minutes. You can set personal options in Dynamics 365 for Outlook to change how often data is synchronized, but you can’t synchronize data more frequently than every 15 minutes. If you need to synchronize right away, you can do a manual synchronization.
In Dynamics 365 for Outlook, click File > Dynamics 365 > Synchronize > Start Synchronization.
If you receive the error message "Dynamics 365 server Not Found", verify that you have Internet connectivity and that the Dynamics 365 server is running. Then try synchronizing again.