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Auto update the .NET core versions on your server

.NET Full Framework updates on your server(s) become available as Windows Updates and can be pushed through centralized tools like Microsoft Intune, System Center Configuration Manager (SCCM), or Windows Server Update Services (WSUS), allowing IT ops teams to control update scheduling and minimize unexpected downtime.

However such an option didn’t exist for a long time for .NET Core. This changed some time ago when .NET Core updates became available via Microsoft Updates as an opt-in(!) feature.

How to enable automatic updates for .NET Core

Enabling automatic .NET updates on your Windows Server requires modifying the Windows Registry. You have several options depending on your needs:

Enable All .NET Updates (Recommended for most scenarios):

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NET]
"AllowAUOnServerOS" = dword:00000001

Version-Specific Updates:

  • .NET 9.0: [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NET\9.0]
  • .NET 8.0: [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NET\8.0]

Each version-specific key uses the same value: "AllowAUOnServerOS" = dword:00000001

Remark: If you are using an centralized configuration tool like Microsoft Intune, this feature is probably not for you.

Application impact

This feature will only push minor updates and NOT automatically switch your app to a newer .NET Core version. Minor updates to .NET Core—such as going from version 8.0.1 to 8.0.8—typically brings security patches, bug fixes, and performance improvements, but it’s designed to be non-breaking. That means your applications built on earlier minor versions (like 8.0.1) should continue to run smoothly on newer ones (like 8.0.8) without requiring code changes.

Here’s a breakdown of what you can expect:

  • Runtime Compatibility: Apps built with .NET Core 8.0.1 will generally run fine on 8.0.8. Minor updates maintain backward compatibility within the same major version.

  • Security Enhancements: These updates often patch vulnerabilities, so not applying them could expose your server to risks.

  • Bug Fixes: Minor updates may resolve runtime or framework bugs that could affect stability or performance.

  • No API Changes: Microsoft avoids introducing new APIs or removing existing ones in minor updates, so your codebase remains unaffected.

More information

.NET and .NET Framework September 2025 servicing releases updates - .NET Blog

.NET Automatic Updates for Server Operating Systems - .NET Blog

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