January 22, 2019 — KB4481031 Cumulative update for .NET Framework 3.5 and 4.7.2 for Windows 10, version 1809 and Windows Server 2019

Applies to: .NET Framework

Improvements and fixes

This update includes quality improvements. No new operating system features are being introduced in this update. Key changes include:

  • Addresses a garbage collection issue in JIT-compiled code.
  • Addresses a race condition that affects IIS-hosted Net.tcp WCF services when the portsharing service is restarted, causing the service to become unavailable.
  • Addresses issues that are related to: 
    • Special mode in which the logical call context is not serializable, causing SerializationException when secondary app domains call back to the default domain to collect evidence.
    • Special mode in which the thread is running under an impersonated user token instead of the primary process token. This causes COMException when evidence examination triggers urlmon initialization in the system. And that activity, in turn, fails because it assumes a level of registry access that is not always present during impersonation.
  • Addresses an issue in Windows Forms applications that may not be able to render the application UI and, instead, render a white screen that contains a red "X" symbol.


Known issues in this update

For 24 hours, this Jan 22, 2019 Cumulative Update for .NET Framework 3.5 and 4.7.2 (KB4481031) was made available broadly on Windows Update as an automatic update. As of January 23, 2019, this update is no longer offered on Windows Update as an automatic update, but rather only to "seekers" who go to Settings > Update & Security > Windows Update, and then select Check for updates, as is expected.  This update continues to be available on WSUS and Microsoft Update Catalog.

How to get this update

Install this update

To download and install this update, go to Settings > Update & Security > Windows Update and select Check for updates.

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

File Information

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.

Windows 10

Additional file information