Preview of Quality Rollup for .NET Framework 4.8 for Windows 7 SP1 and Windows Server 2008 R2 SP1 (KB4531182)

Applies to: .NET Framework

The November 19, 2019 update for Windows 7 SP1 and Server 2008 R2 SP1 includes cumulative reliability improvements in .NET 4.8. 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

  • Starting in August, 2019, updates to .NET Framework 4.6 and above, for Windows Server 2008 SP2, Windows Server 2008 R2 SP1, and Windows 7SP1, require SHA-2 Code signing support. Please make sure that you have all the latest Windows Updates before applying this update to avoid installation issues. For more detailed information about SHA-2 code signing support updates, please see KB 4474419.

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.

WPF1

Addresses and issue where some Per-Monitor Aware WPF applications that host System-Aware or Unaware child-windows running on .NET Framework 4.8 may occasionally encounter a crash with exception System.Collections.Generic.KeyNotFoundException.

CLR2

Addresses and issue where some ClickOnce applications or applications creating the default AppDomain with a restricted permission set may observe application launch or application runtime failures, or unexpected behaviors. The observable issue was the System.AppDomainSetup.TargetFrameworkName is null, leading to any quirks enabling reverting back to .NET Framework 4.0 behaviors.


1 Windows Presentation Foundation (WPF)
2 Common Language Runtime (CLR)

Known Issues in this update


There are no known issues with this update, however, this update resolves a previous known issue. This patch includes improvements to resolve a known issue discussed in KB4519568 that occurs after applying the October Preview of Quality Rollup for .NET Framework 4.8. To resolve this issue, install update for .NET Framework 4.8 for Windows 7 SP1 and Windows Server 2008 R2 SP1 KB4533005.

Additional information about this update


The following articles contain additional information about this update as it relates to individual product versions.
 
  • 4524741 Description of the Preview of Quality Rollup for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows 7 SP1 and Server 2008 R2 SP1 (KB4524741)

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 4524741 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 4.8 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 4520406.

File information


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

 

How to obtain help and support for this update