Consider the following scenario. You create a custom entity in Microsoft Dynamics CRM. You mark Available Offline, and then you publish the customizations.
When you go into Microsoft Dynamics CRM for Microsoft Office Outlook, one of the following symptoms is true:
The custom entity does not appear in the left navigation.
You are able to open the custom entity, but the "New" button is not available in the ribbon.
The Sitemap is refreshed on an hourly basis, so it may take some time for the new custom entity to appear in Microsoft Dynamics CRM for Microsoft Office Outlook.
Wait for approximately an hour before you attempt to access a new custom entity in Microsoft Dynamics CRM for Microsoft Office Outlook.