Preview of Quality Rollup for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows 8.1, RT 8.1, and Server 2012 R2 (KB4524420)

Applies to: .NET Framework

The November 19, 2019 update for Windows 8.1, RT 8.1, and Server 2012 R2 includes cumulative reliability improvements in .NET 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2. We recommend that you apply this update as part of your regular maintenance routines. Before you install this update, see the Prerequisites and Restart requirement sections.

Important

  • All updates for Windows 8.1, Windows RT 8.1, and Windows Server 2012 R2 require that update KB 2919355 is installed. We recommend that you install update KB 2919355 on your Windows 8.1-based, Windows RT 8.1-based, or Windows Server 2012 R2-based computer so that you receive updates in the future.
  • If you install a language pack after you install this update, you must reinstall this update. Therefore, we recommend that you install any language packs that you need before you install this update. For more information, see Add language packs to Windows.

Quality and reliability improvements


ASP.NET

ASP.NET will now emit a SameSite cookie header when HttpCookie.SameSite value is "None" to accommodate upcoming changes to SameSite cookie handling in Chrome. As part of this change, FormsAuth and SessionState cookies will also be issued with SameSite = 'Lax' instead of the previous default of 'None', though these values can be overridden in web.config.

CLR2 Addresses an issue where System.Windows.Forms.ComboBox control with ImeMode set to ImeMode.NoControl on CHS with Pinyin keyboard retained input mode of the parent container control instead of switching to disabled IME when navigating using mouse clicks and when focus moves from a control with disabled IME to this ComboBox control.
SQL Addresses an issue with SqlClient Bid traces where information wasn't being printed due to incorrectly formatted strings.
WCF1

Addresses a race condition when using WCF TCP Port Sharing where a client which disconnects part way through the session establishment handshake can result in the WCF Service no longer being able to accept new connections.

When an IIS worker process has many WCF TCP web services using TCP Port Sharing and the worker process crashes while under high CPU load, a race condition during TCP Port sharing reinitialization can result in some endpoints not being able to accept client connections. Added an AppSetting to enable retrying initialization when this happens.


1 Windows Communication Foundation (WCF)
2 Common Language Runtime (CLR)

Additional information about this update


The following articles contain additional information about this update as it relates to individual product versions.
  • 4524743 Description of the Preview of Quality Rollup for .NET Framework 3.5, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows 8.1, RT 8.1, and Server 2012 R2 (KB4524743)

How to obtain and install the update


Method 1: Windows Update

This update is available through Windows Update. Go to Settings > Update and Security > Windows Update, and then select Check for updates. For more information about how to get preview updates, see Windows Update: FAQ.

Method 2: Microsoft Update Catalog

To get the standalone package for this update, go to the Microsoft Update Catalog website.

Method 3: Windows Software Update Services (WSUS)

On your WSUS server, follow these steps:

  1. Select Start, select Administrative Tools, and then select Microsoft Windows Server Update Services 3.0.
  2. Expand ComputerName, and then select Action.
  3. Select Import Updates.
  4. WSUS opens a browser window in which you may be prompted to install an ActiveX control. You must install the ActiveX control to continue.
  5. After the ActiveX control is installed, you see the Microsoft Update Catalog screen. Type 4524743 into the Search box, and then select Search.
  6. Locate the .NET Framework packages that match the operating systems, languages, and processors in your environment. Select Add to add them to your basket.
  7. After you select all the packages that you require, select View Basket.
  8. To import the packages to your WSUS server, select Import.
  9. After the packages are imported, select Close to return to WSUS.

The updates are now available for installation through WSUS.

Prerequisites

To apply this update, you must have .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 installed.

Restart requirement

You must restart the computer after you apply this update if any affected files are being used. We recommend that you exit all .NET Framework-based applications before you apply this update.

Update replacement information

This update replaces previously released updates 4520408.

File information


The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.

Windows 8.1, Windows RT 8.1 and Windows Server 2012 R2

Additional file information

How to obtain help and support for this update