If you need to enable the initial custom entity sync to make data from Dynamics available in Marketo, here's how to do it.
Admin Permissions Required
Make sure the initial sync is completed (you will be notified via email) before beginning the sync for custom entities.
1. Go to the Admin section.
2. Click Disable Sync to temporarily disable the standard global sync.
3. Install a version of Microsoft Dynamics that supports custom entity sync (after 2_0_0_2). See Marketo Plugin Releases for MIcrosoft Dynamics.
4. Give the Marketo Sync User read access to any entities you plan to sync.
5. Under Database Management, click the Dynamics Entities Sync link.
6. Click the Sync schema link to bring over the list of available custom entities.
7. After the list syncs, select the fields you want to sync and ones you want to use as constraints and/or triggers in smart lists. When done, click Enable Sync.
8. Re-enable the global sync.
Marketo only supports custom entities that are linked to standard entities one or two levels deep.
Entity names can have a maximum of 33 characters.