February 11, 2020
.NET Framework 3.5 and 4.7.2
This update for Windows 10 Version 1809 and Windows Server 2019 includes cumulative reliability improvements in .NET 3.5 and 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.
This update is included in the Cumulative Update that is dated February 11, 2020. This update was previously released in the Cumulative Update that was dated January 23, 2020.
Quality and reliability improvements
- Addresses a hang and eventual StackOverflowException arising when opening a RibbonSplitButton, if the app programmatically disables the button and replaces its menu items before the user releases the mouse button.
- Addresses a reliability problem that reduces crashes when running in Software Rendering mode.
- Addresses a hang arising during layout of Grids with columns belonging to a SharedSizeGroup.
- Addresses certain hangs that can arise while scrolling a TreeView.
- Addresses an issue in System.Windows.Forms.TextBox controls with ImeMode property set to NoControl. These controls now retain IME setting consistent with the OS setting regardles of the order of navigation on the page. Fix applies to CHS with pinyin keyboard.
- Addresses an issue with System.Windows.Forms.ComboBox control with ImeMode set to ImeMode.NoControl on CHS with Pinyin keyboard to retain 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.
- Added opt-in retry mechanism when configuring listening endpoints on the WCF Activation service to address potential race condition when rapidly restarting an IIS application multiple times while under high CPU load which resulted in an endpoint being inaccessible. Customers can opt in to the fix by adding the following AppSetting to SMSvcHost.exe.config under the %windir%\Microsoft.NET\Framework\v4.0.30319 and %windir%\Microsoft.NET\Framework64\v4.0.30319 folders as appropriate. This will retry registering an endpoint 10 times with a 1 second delay between each attempt before placing the endpoint in a failure state.
- There is a race condition in the portable PDB metadata provider cache that leaked providers and caused crashes in the diagnostic StackTrace API. To fix the race, detect the cause where the provider wasn't being disposed and dispose it.
- Addresses an issue with SqlClient Bid traces where information wasn’t being printed due to incorrectly formatted strings.
1 Windows Presentation Foundation (WPF)
2 Windows Communication Foundation (WCF)
3 Common Language Runtime (CLR)
Additional information about this update
- 4538122 Description of the Cumulative Update for .NET Framework 3.5, 4.7.2 and 4.8 for Windows 10 Version 1809 and Windows Server 2019 (KB4538122)
How to obtain and install the update
Install this update
This update will be downloaded and installed automatically from Windows Update.
To get the standalone package for this update, go to the Microsoft Update Catalog website.
For a list of the files that are provided in this update, download the file information for cumulative update .
To apply this update, you must have .NET Framework 3.5 or 4.7.2 installed.
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.