Microsoft Support:
March 27, 2025 - KB5054979 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11, version 24H2
IMPORTANTThis update was originally released in the Security and Quality Rollup that’s dated April 8, 2025. This update is included in the Security and Quality Rollup that’s dated April 8, 2025.
There is no change to this update with this release on April 8, 2025. If you have previously installed this update no action is needed.
The March 27, 2025 update for Windows 11, version 24H2 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.
Summary
Security ImprovementsThere are no new security improvements in this release. This update is cumulative and contains all previously released security improvements.
Quality and Reliability Improvements
| .NET Fundamentals | - Addresses an issue where System.IO APIs are used to operate on files and directories on UNC shares. |
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 | Yes | Go to Settings > Update & Security > Windows Update. In the Optional updates available area, you’ll find the link to download and install the update. |
| Windows Update for Business | Yes | Go to Settings > Update & Security > Windows Update. In the Optional updates available area, you’ll find the link to download and install the update. |
| Microsoft Update Catalog | Yes | To get the standalone package for this update, go to the Microsoft Update Catalog website. |
| Windows Server Update Services (WSUS) | Yes | This update will automatically sync with WSUS if you configure Products and Classifications as follows: Product: Windows 11, version 24H2 and Microsoft server operating system version 24H2 Classification: Updates |
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. Source:
Last edited:
