I’m really happy to announce the release of the 3 rd CTP for the Open XML SDK 2.0 for Microsoft Office ! So what did we do in this CTP? Well, there were three main improvements we made to the SDK: Add semantic level validation support Add markup compatibility/extensibility support General improvements based on your feedback Semantic Level Validation Support Let’s go back to the Open XML SDK architecture diagram I showed you when we first announced the Open XML SDK : As mentioned in a previous post , the April 2009 CTP of the Open XML SDK added schema level validation support for Office 2007 Open XML files

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Announcing the Release of the August 2009 CTP for the Open XML SDK