Microsoft is implementing four new interoperability principles and corresponding actions across its high-volume business products:

(1) ensuring open connections
(2) promoting data portability
(3) enhancing support for industry standards
(4) fostering more open engagement with customers and the industry, including open source communities.

Read the full Microsoft PressPass article.

The Windows Vista and Windows Server TechCenters have been updated with documentation, as well downloads and forums

Windows Open Protocols Online Documentation

Introduction

Microsoft is providing access through open connections to its high-volume products—Windows Vista (including the .NET Framework), Windows Server 2008, SQL Server 2008, Office 2007, Exchange Server 2007, and Office SharePoint Server 2007—so that software developers, business partners, and competitors can better interact with these Microsoft products or invent new solutions for customers.

Windows Communication Protocols

The Microsoft Communications Protocol Program (MCPP) technical documentation set provides detailed technical specifications for Microsoft proprietary protocols (including extensions to industry-standard or other published protocols) that are implemented and used in Windows client operating systems (namely Windows 2000 Professional and successors up to and including Windows Vista) to interoperate or communicate natively with Windows Server operating systems (namely Windows NT 3.1 up to and including Windows Server 2008). The documentation set includes a set of companion overview and reference documents that supplement the technical specifications with conceptual background, overviews of inter-protocol relationships and interactions, and technical reference information, such as common data types and error codes.

Windows Server Protocols

The Work Group Server Protocol Program (WSPP) technical documentation set provides detailed technical specifications for Microsoft proprietary protocols (including extensions to industry-standard or other published protocols) that are implemented in Microsoft Windows Server work group server software and that are used to deliver file & print and user & group administration services to Windows work group networks. The documentation set includes a set of companion overview and reference documents that supplement the technical specifications with conceptual background, overviews of inter-protocol relationships and interactions, and technical reference information, such as common data types and error codes.

Important notes about the documentation

• “Copy Code” button does not currently work in Firefox
  It is a known issue that the “Copy Code” button that appears on code samples in an Open Protocols specification does not copy code to the clipboard when the specification is viewed in the Firefox Web browser. Instead of using the button, highlight the code and copy it.
  
• Download PDF documents to the same directory to retain links
  If you use the PDF versions of the Open Protocols specifications, be sure to download all of the documents to the same directory. Hyperlinks between specifications require the documents to be in the same directory to work.
  
• Byte Array diagram formatting is richer in the PDF version
  Formatting of byte-array data is simplified in the on-line version of the documents. Implementers may find it useful to review the PDF version of an Open Protocol specification for a richer formatted version of a byte-array diagram.
  
• “End Note” links are misdirected to MS-SECO
  It is a known issue that links in the on-line version of an Open Protocol specification misdirect to MS-SECO rather than going to Appendix A: Windows Behavior in the same specification. These links are easily identified as a number enclosed in triangle-brackets, i.e., <1>. These links work correctly in the PDF version of the specification.