How to: Connect External Lists to Outlook

SharePoint 2010

Last modified: April 16, 2010

Applies to: SharePoint Server 2010

External lists in Microsoft SharePoint Server 2010 can be connected to Microsoft Outlook 2010 (also known as "taking offline" in Outlook) to enable users to work on external data in the familiar Outlook user interface. Outlook will display the data from the external list in a managed PST folder named BCSStorage.PST. Users will be able to create, read, update, and delete external data (for example, sales or customer data from an external data source) from within Outlook just like they would create, read, or delete an Outlook item such as a task or an appointment. When creating external content types, you can decide whether to enable users to take external lists based on this external content type offline in Outlook and if so, then decide what out-of-the-box Outlook item type this external content type closely maps to. The supported types are:

  • Contact

  • Task

  • Appointment

  • Post

When you map an external content type such as Customer to an Outlook ItemType such as Contact, you need to also map the fields of the Customer from the external system such as FirstName, LastName, Address, and Phone to the respective Outlook Contact item's properties so they are mapped correctly in the Outlook inspector and views. The following table shows the mandatory fields that you need to map for each Outlook item type.

Outlook Item Type

Outlook Item Field






Start, End, and Subject



For fields that do not map to the existing Outlook item properties, you do not need to do any mapping; these will be displayed as Microsoft Business Connectivity Services (BCS) extended properties in the adjoining form region of the Outlook inspector if the number of such fields is less than or equal to five, and in a separate form region if the number of such fields is greater than five. The following table describes what these regions mean. For more information, see How to: Create External Content Types.


Adds the form region as a new page in an Outlook form.


Appends the form region to the bottom of an Outlook form's default page.

Note Note

If the external content type does not map directly to any of the previously described supported types in Outlook, you can either take the list offline in Microsoft SharePoint Workspace or if you need to bring external data to Outlook, then you can map it to a Post item in Outlook as it is the most generic type of item. Business Connectivity Services will display the fields that are not mapped to the default Post item properties in the adjoining or in a separate form region, depending on the number of such fields as described earlier.