There are two types of synchronization with Microsoft Dynamics CRM Online for Outlook: synchronization with Outlook and synchronization with local data.
If you have Microsoft Dynamics CRM Online for Outlook with Offline Access installed on your computer, you can work offline with Microsoft Dynamics CRM Online data. When you go offline, Microsoft Dynamics CRM Online copies a subset of the data on the Microsoft Dynamics CRM Online server to your computer. This local data is defined by a local data group and by the synchronization options set in your personal options.
After you go back online, changes you made to your local data are updated to the Microsoft Dynamics CRM Online server. If you encounter problems during synchronization, you are given choices on how to continue. You may also be notified of duplicate records.
Set synchronization options in Microsoft Dynamics CRM Online for Outlook
Set address book options in Microsoft Dynamics CRM Online for Outlook
Synchronize with Outlook manually
Resolve data synchronization errors
Define filters for data to take offline