Framework 3.5 Service Pack 1

Microsoft .NET Framework 3.5 Service Pack 1 is a full cumulative update that contains many new features building incrementally upon .NET Framework 2.0, 3.0, 3.5, and includes cumulative servicing updates to the .NET Framework 2.0 and .NET Framework 3.0 subcomponents.


Some of the new features and improvements:

Core improvements to the CLR (common language runtime) that include better layout of .NET Framework native images, opting out of strong-name verification for fully trusted assemblies, improved application startup performance, better generated code that improves end-to-end application execution time, and opting managed code to run in ASLR (Address Space Layout Randomization) mode if supported by the operating system. Additionally, managed applications that are opened from network shares have the same behavior as native applications by running with full trust.

Performance improvements to WPF (Windows Presentation Foundation), including a faster startup time and improved performance for Bitmap effects. Additional functionality for WPF includes better support for line of business applications, native splash screen support, DirectX pixel shader support, and the new WebBrowser control.

Windows Communication Foundation now makes the DataContract Serializer easier to use by providing improved interoperability support, enhancing the debugging experience in partial trust scenarios, and extending syndication protocol support for wider usage in Web 2.0 applications.

The .NET Framework Data Provider for SQL Server (SqlClient) adds new support for file stream and sparse column capabilities in SQL Server 2008.

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http://www.microsoft.com/downloads/details.aspx?familyid=ab99342f-5d1a-413d-8319-81da479ab0d7&displaylang=en