Client Object Model with the Open XML SDK

The Microsoft SharePoint Foundation 2010 managed client object model enables you to write applications that are based on the Microsoft .NET Framework that access SharePoint content from clients without installing code on the server that runs SharePoint Foundation 2010. 

The Open XML SDK 2.0 for Microsoft Office enables you to write applications to create, change, and query Open XML documents, the default document format for the Microsoft 2007 Office system and Microsoft Office 2010. By using these two technologies together you can write client-side applications that work with Open XML documents that are stored in document libraries.

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