Microsoft .NET Framework 3.5 Microsoft .NET Framework 4.5.2 Microsoft .NET Framework 4.6 Microsoft .NET Framework 4.6.1 Microsoft .NET Framework 4.6.2 Microsoft .NET Framework 4.7 Microsoft .NET Framework 4.7.1 Microsoft .NET Framework 4.7.2 Microsoft .NET Framework 4.8
This update is included in the Security and Quality Rollup that's dated September 8, 2020. Parts of this update were previously released in the rollup that's dated August 11, 2020.
ClickOnce will no longer download applications from untrusted servers which use NTLM authentication, but, instead, will fail with “Authentication failed”. Sites in the Local Intranet and Trusted sites zones will continue to authenticate as before.
For a list of improvements that were released with this update, please see the article links in the Additional Information section of this article.
As a reminder to advanced IT administrators, updates to .NET Framework 3.5 for Windows 8.1 and Windows Server 2012 R2 should only be applied on systems where .NET Framework 3.5 is present and enabled. Customers who attempt to pre-install updates to .NET Framework 3.5 to offline images that do not contain the .NET Framework 3.5 product enabled will expose these systems to failures to enable .NET Framework 3.5 after the systems are online. For more extensive information about deploying .NET Framework 3.5, see Microsoft .NET Framework 3.5 Deployment Considerations.
All updates for Windows 8.1, Windows RT 8.1, and Windows Server 2012 R2 require that update KB 2919355 is installed. We recommend that you install update KB 2919355 on your Windows 8.1-based, Windows RT 8.1-based, or Windows Server 2012 R2-based computer so that you receive updates in the future.
If you install a language pack after you install this update, you must reinstall this update. Therefore, we recommend that you install any language packs that you need before you install this update. For more information, see Add language packs to Windows.
Additional information about this update
The following articles contain additional information about this update as it relates to individual product versions.
4569768 Description of the Security and Quality Rollup for .NET Framework 3.5 for Windows 8.1, RT 8.1, and Windows Server 2012 R2 (KB4569768)
4569778 Description of the Security and Quality Rollup for .NET Framework 4.5.2 for Windows 8.1, RT 8.1, and Windows Server 2012 R2 (KB4569778)
4576614 Description of the Security and Quality Rollup for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows 8.1, RT 8.1, and Windows Server 2012 R2 (KB4576614)
4576486 Description of the Security and Quality Rollup for .NET Framework 4.8 for Windows 8.1, RT 8.1, and Windows Server 2012 R2 (KB4576486)