March 26, 2024 - KB5036035 Cumulative Update Preview for .NET Framework 3.5 and 4.8.1 for Windows 11, version 23H2
Applies To
.NETRevised July 7, 2025: Updated 'How to get this update' section.Â
Release Date:
March 26, 2024Version:
.NET Framework 3.5 and 4.8.1The March 26, 2024 update for Windows 11, version 23H2 includes security and cumulative reliability improvements in .NET Framework 3.5 and 4.8.1. 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.Â
Summary
Security Improvements
There are no new security improvements in this release. This update is cumulative and contains all previously released security improvements.
Quality and Reliability Improvements
There are no new Quality and Reliability Improvements in this update.
.NET Libraries |
- Addresses a performance issue in ASP.NET applications after installing the January 2024 .NET Framework update. |
.NET Runtime |
- Addresses an issue when thread pool recycled lists become unresponsive on multi-CPU-group computers. - Addresses an issue where Interlocked.Read from 32-bit apps are much slower on some computers. |
.NET Compilers |
- Addresses an issue when using the native C# compiler (csc.exe) to compile code making calls to COM interop assemblies. |
Known issues in this update
Microsoft is not currently aware of any issues in this update.
How to get this update
Install this update
Release Channel |
Available |
Next Step |
Windows Update and Microsoft Update |
No |
See note |
Windows Update for Business |
No |
See note |
Microsoft Update Catalog |
No |
See note |
Windows Server Update Services (WSUS) |
No |
See note |
Note: This update is no longer available. At this time, no functional issues have been reported with this update. To ensure your device continues to receive the latest security updates and quality improvements, we recommend installing the most recent cumulative update.
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 4.8.1 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.
How to obtain help and support for this update
-
Help for installing updates: Windows Update FAQ
-
Protect yourself online and at home: Windows Security support
-
Local support according to your country: International Support