Skip to main content

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

Popular posts from this blog

Podman– Command execution failed with exit code 125

After updating WSL on one of the developer machines, Podman failed to work. When we took a look through Podman Desktop, we noticed that Podman had stopped running and returned the following error message: Error: Command execution failed with exit code 125 Here are the steps we tried to fix the issue: We started by running podman info to get some extra details on what could be wrong: >podman info OS: windows/amd64 provider: wsl version: 5.3.1 Cannot connect to Podman. Please verify your connection to the Linux system using `podman system connection list`, or try `podman machine init` and `podman machine start` to manage a new Linux VM Error: unable to connect to Podman socket: failed to connect: dial tcp 127.0.0.1:2655: connectex: No connection could be made because the target machine actively refused it. That makes sense as the podman VM was not running. Let’s check the VM: >podman machine list NAME         ...

Cache stampede: when our cache turned against us

While investigating some performance issues, we ran into an ASP.NET Core API that cached a fairly expensive aggregation query for 60 seconds. Under normal load, that was fine: one request rebuilds the cache, everyone else reads from it. Under peak load, dozens of requests would arrive in that same expiry window, all see a cache miss, and all fire the same expensive query in parallel. The database didn't like that. That was the moment when our caching layer stopped helping and started hurting. A burst of requests comes in at the same time, all miss the cache, and all go hammer the database or the downstream API at once. That's a cache stampede . The cache was supposed to protect our backend, and for a few hundred milliseconds it did the opposite. Why this happens IMemoryCache.GetOrCreate (and its async sibling) looks like it protects you, but it doesn't add any locking on its own. Look at the naive version: public async Task<Report> GetReportAsync(string key) ...

Azure DevOps/ GitHub emoji

I’m really bad at remembering emoji’s. So here is cheat sheet with all emoji’s that can be used in tools that support the github emoji markdown markup: All credits go to rcaviers who created this list.