June 21, 2021 - KB5003537 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows 10, version 2004, Windows Server, version 2004, Windows 10, version 20H2, and Windows Server, version 20H2, and Windows Version 21H1
The July 13, 2021 update for Windows 10, version 2004, Windows Server, version 2004, Windows 10, version 20H2, and Windows Server, version 20H2, and Windows Version 21H1 includes cumulative reliability improvements in .NET Framework 3.5 and 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.
Quality and reliability improvements
WPF1 |
- Addresses an issue affecting a DataGrid contained in an outer ScrollViewer.
- Addresses a crash due to ElementNotAvailableException in a ListView with custom data-item automation peers. |
CLR2 |
- When the process is not under high memory pressure it tends to favor doing BGCs over doing full compacting GCs. This is usually desirable but if the app behavior changes dramatically, it could cause much of the fragmentation in older generations (ie, gen2 and LOH) to be unused. You can collect GC ETW events which tell you how much fragmentation there is in gen2 and LOH and verify if you are in this situation. |
Winforms |
- Addresses an issue in Property Grid control to prevent incorrect data read in some scenarios in 64 bit processes.
- Addresses an issue where System.Drawing double frees allocated memory when failing to get printer settings. |
ClickOnce |
- Addresses a regression introduced in previous updates. We now honor WinTrust policy setting "Ignore timestamp revocation checks" setting when validating timestamps in ClickOnce manifests. |
1 Windows Presentation Foundation (WPF)
2 Common Language Runtime (CLR)
How to get this update
Install this update
Release Channel |
Available |
Next Step |
Windows Update and Microsoft Update |
Yes |
To download and install this update, go to Settings > Update & Security > Windows Update, and then select Check for updates. |
Microsoft Update Catalog |
Yes |
To get the standalone package for this update, go to the Microsoft Update Catalog website. |
Windows Server Update Services (WSUS) |
No |
You can import this update into WSUS manually. See the Microsoft Update Catalog for instructions. |
File information
For a list of the files that are provided in this update, download the
file information for cumulative update.
Prerequisites
To apply this update, you must have .NET Framework 3.5 or 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.