.NET Framework 4.7.1 Update (KB4054856)

An update for the .NET Framework 4.7.1 is available for Windows 7 SP1, Windows 8.1, Windows 10 Anniversary Update, Windows 10 Creators Update, Windows Server 2008 R2 SP1, Windows Server 2012, Windows Server 2012 R2, and Windows Server 2016. For more information about the issues that this update resolves, see the "Issues that this update resolves" section. The fixes in this update will be available in an upcoming Cumulative Update for Fall Creators Update (Version 1709) and Server 2016 Version 1709.

Windows Update

This update is available from Windows Update.

Microsoft Download Center

The following file is available for download from the Microsoft Download Center:

Download the package now

For Windows RT 8.1:

Download the package now

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

Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to the file.

Prerequisites

To apply this update, you must have .NET Framework 4.7.1 installed.

Restart requirement

You do not have to restart the computer after you apply this update if the affected files are not being used.

The following problems in .NET Framework 4.7.1 are fixed in this update.

Base Class Library (BCL)

• Applications targeting .NET 4.6.1 that use .NET Standard libraries might be broken when running on .NET Framework 4.7.1. [526755, netstandard.dll, Bug]
• CultureAwareComparer with ignore casing serialized on previous versions of .NET Framework does not correctly deserialize on .NET Framework 4.7.1.  [526752, mscorlib.dll, Bug]
• Applications making heavy use of System.Diagnostics.StackTrace or Exception.StackTrace might run more slowly on the .NET Framework 4.7.1. [517815, System.dll, Bug]

Windows Presentation Framework (WPF)

• Certain dual GPU machines may experience visual artifacts while running WPF apps in high contrast. [530113, System.Drawing.dll, Bug]
• In specific scenarios, the System.Windows.Controls.PrintDialog() throws an Arithmetic Overflow exception. [530512, PresentationFramework.dll, Bug]

When you install this package, you can see that the following updates were installed, depending on your operating system:

• On Windows 7 SP1 and Windows Server 2008 R2 SP1, Update for Microsoft.NET Framework 4.7.1 (KB4054852) is listed as an installed product under the Programs and Features item in Control Panel.
• On Windows Server 2012, it’s listed as Update for Microsoft Windows (KB4054853) under the Installed Updates item in Control Panel.
• On Windows 8.1 or Windows Server 2012 R2, it's listed as Update for Microsoft Windows (KB4054854) under the Installed Updates item in Control Panel.
• On Windows 10 Anniversary Update, Windows 10 Creators Update and Windows Server 2016 it’s listed as Update for Microsoft Windows (KB4054855) under the Installed Updates item in Control Panel.

Troubleshooting

While installing this update, one might encounter an issue that prevents or blocks the installation of this update. The following table lists possible blocking issues and provides respective resolutions.

This update for .NET Framework 4.7.1 is supported on the following operating systems:

• Windows 7 Service Pack 1 (x86 and x64)
• Windows 8.1 (x86 and x64)
• Windows 10 Anniversary Update / Version 1607 (x86 and x64)
• Windows 10 Creators Update / Version 1703 (x86 and x64)
• Windows Server 2008 R2 Service Pack 1 (x64)
• Windows Server 2012 (x64)
• Windows Server 2012 R2 (x64)
• Windows Server 2016 (x64)

The fixes in this update will be available in the Cumulative Update for Fall Creators Update (Version 1709) and Server 2016 Version 1709.