The .NET Framework 4.5.1 RC Developer Pack installs the multi-targeting pack for .NET Framework 4.5.1 RC using which a developer can build .NET Framework 4.5.1 based applications. If you intend to redistribute the .NET Framework 4.5.1 you should download the web installer instead.
The .NET Framework 4.5.1 RC is a highly compatible, in-place update to the .NET Framework 4 and the .NET Framework 4.5. These packages can be used on the operating systems listed in the "Supported Operating Systems" section on this page. The developer pack also installs the multi-targeting pack for the .NET Framework 4.5.1; you can use this pack to use Visual Studio 2012 to build applications based on the .NET Framework 4.5.1.
This package installs these components:
- .NET Framework 4.5.1 RC
- .NET Framework 4.5.1 Multi-Targeting Pack RC, which contains the reference assemblies that are required to build apps that target the .NET Framework 4.5.1, and the IntelliSense files that are required to display Help when you are using Visual Studio to build apps that target the .NET Framework 4.5.1.
This version of the .NET Framework runs side-by-side with the .NET Framework 3.5 SP1 and earlier versions, but performs an in-place update for the .NET Framework 4 and the .NET Framework 4.5. The .NET Framework 4.5.1 is already included in Windows 8.1 and Windows Server 2012 R2.
For more information, see the Knowledge Base Article KB2872781.
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