Business Data Connectivity Service allow to connect with external data system (WCF service, database, .Net assemblies), which is improved version of formal Business Data Catalog in SharePoint 2007. But you can get this type of error after installing SharePoint 2010 Beta and SharePoint Designer 2010, opening Designer and navigating to the External Content Types object results in the following error: This problem can happen If your SharePoint installed in Windows 7 OS due to the following patch of ......