Standalone installer for .NET Framework 3.5 beta 1 now available for download

Visual Studio codename Orcas beta 1 was recently released, and now a standalone version of the .NET Framework 3.5 beta 1 (which is also installed as a prerequisite during VS Orcas setup) is available as a standalone download on the Microsoft download center.  Here are links to download information for the .NET Framework 3.5 beta 1:

.NET Framework 3.5 setup-specific details

The .NET Framework 3.5 follows a similar model to the .NET Framework 3.0 - it builds on the .NET Framework 2.0 and adds supplemental features.  It is not an entirely new version of the common language runtime (CLR).  Behind the scenes, the .NET Framework 3.5 installs the following (if they are not already present on the system):

  • .NET Framework 2.0
  • .NET Framework 2.0 SP1 beta
  • .NET Framework 3.0
  • .NET Framework 3.0 SP1 beta for Windows Communication Foundation and Windows Workflow Foundation
  • .NET Framework 3.5

The package available for download is a web download bootstrapper.  It will inventory your system and download and install the packages that it detects are not yet installed.

.NET Framework 3.5 features

Some of the key new features introduced in the .NET Framework 3.5 are the following (also summarized on the download page linked above):

  • Deep integration of Language Integrated Query (LINQ) and data awareness
  • ASP.NET AJAX for quickly creating more efficient, more interactive and highly-personalized Web experiences that work across all the most popular browsers
  • New web protocol support for building WCF services including AJAX, JSON, REST, POX, RSS, ATOM and several new WS-* standards
  • New classes in the base class library (BCL) for the .NET Framework 3.5 address the most common customer requests.

Getting help from the community

If you encounter issues while installing or using the .NET Framework 3.5 beta 1 or Visual Studio codename Orcas beta 1, there are several community forums available at  For setup-related issues, you can use the following forums:

Reporting bugs found in the beta version

Also, most importantly, if you run into problems while installing or using the .NET Framework 3.5 beta 1 and/or Visual Studio codename Orcas, please help us make the final release as good as it can be by reporting bugs back to Microsoft.  You can use the site at to report bugs or suggestions for these beta products.

I have seen countless cases where bugs reported by end users that could not be reproduced in our test labs at Microsoft have been fixed (such as this tricky issue in the .NET Framework 2.0), so I assure you that every bug report is reviewed by team members here at Microsoft and they are taken very seriously.