U BCSSync BCSSync.exe "Part of SharePoint Server 2010 which is part of the Microsoft Office 2010 suite. ""Business Connectivity Services (BCS) uses a cache to store a copy of the external data required by the BCS solutions deployed on the Office client. A process called BCSSync.EXE runs on the client and provides automatic cache refresh and data synchronization of the entity instances."" For more information - see here"