Generally speaking, you can assume that a mailbox will be synced at least once every 12 minutes. If the mailbox is less active, the interval can be increased up to 12 minutes. When a mailbox has many email messages, the interval can be reduced dynamically to 2 minutes. Normally, email synchronization occurs every 5 minutes. The synchronization algorithm ensures that mailboxes are synced according to dynamic parameters such as the number of email messages and the activity within the mailbox. If you synchronize records with server-side synchronization, the process is dynamic and unique for each user’s mailbox. How often are records synchronized through server-side sync? More information: Integrate your email system To use Dynamics 365 App for Outlook, you must synchronize email with server-side synchronization. They can also link email, appointment, and contact records to new or existing Customer Engagement (on-premises) records, such as opportunity, account, or case records. For example, people can preview information about contacts and leads stored in Customer Engagement (on-premises) and add Customer Engagement (on-premises) contacts directly from an email message. With Dynamics 365 App for Outlook, Customer Engagement (on-premises) information appears next to a user’s Outlook email messages or appointments. You can use Dynamics 365 App for Outlook together with Microsoft Outlook on the web, the Outlook desktop application, or with Outlook mobile. Use Dynamics 365 App for Outlook paired with server-side synchronization to view Customer Engagement (on-premises) data in Outlook and track Outlook records in Microsoft Dynamics 365. There are three ways to use Dynamics 365 Customer Engagement (on-premises) and Outlook together:

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