This article describes the Microsoft .NET Framework 4.5.1 and its corresponding language packs. These are available on Windows Update and Windows Server Update Service (WSUS) for Windows Vista Service Pack 2 (SP2), Windows 7 Service Pack 1 (SP1), Windows Server 2008 SP2, and Windows Server 2008 R2 SP1.
This update is released on Windows Update on all supported platforms as follows:
The .NET Framework 4.5.1 product is offered as a Recommended update.
The .NET Framework 4.5.1 Language Packs are offered as a Recommended update. The computers that have the .NET Framework 4.5.1 and that also contain older versions of language packs for the .NET Framework 4 and the .NET Framework 4.5 will receive this update. This update upgrades all the previous language packs to 4.5.1.
The .NET Framework 4.5.1 Language Packs are also available separately as an Optional update. However, this update is not offered together with the .NET Framework 4.5.1 Recommended update that is described in the second bullet. Computers that meet the following criteria will receive this update:
The .NET Framework 4.5.1 is already installed.
There are no previous .NET Framework 4 or .NET Framework 4.5 language packs installed.
The base operating system is a localized version of Windows, or the computer has one or more Multilingual User Interface (MUI) packs installed. This corresponds to the 23 supported languages for the .NET Framework 4.5.1.
For more information about the .NET Framework supported languages, go to the following MSDN webpage:
On Windows Update, a Recommended update may be installed automatically on all supported platforms, based on your computer settings. Optional updates can only installed by manually selecting the update from the list of available updates.
On Windows 8, you can also install the Microsoft .NET Framework 4.5.1 by upgrading the computer to Windows 8.1.
For more information about the .NET Framework 4.5.1 or the .NET Framework Developer Center, go to the following Microsoft website:
For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:
119591 How to obtain Microsoft support files from online services
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You may have to restart the computer after you install this update. We recommend that you exit all applications that are using the .NET Framework before you install this update.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates