You must install or update .NET to run this application 🟪 .NET

The framework 'Microsoft.NETCore.App', version '8.0.0' (x64) was not found. You must install or update .NET to run this application

The machine doesn’t have the .NET runtime version the app was built for (framework-dependent deployment).

Seen on: .NET

Meaning

Framework-dependent apps need the exact major runtime (and ASP.NET Core runtime for web apps). Install it, roll forward, or publish self-contained.

Common causes

  • Runtime not installed (or only SDK of another version)
  • ASP.NET Core runtime missing (Microsoft.AspNetCore.App)
  • Architecture mismatch (x86 vs x64)
  • Docker base image with older runtime

⚡ Quick fix

  1. Install the runtime/Hosting Bundle for that version
  2. Publish self-contained (--self-contained -r linux-x64)
  3. Use the matching Docker base image (mcr.microsoft.com/dotnet/aspnet:8.0)

Detailed fix by platform

Shell

  1. csharp
    dotnet --list-runtimes
dotnet publish -c Release -r linux-x64 --self-contained true

How to diagnose

  1. Installed — dotnet --list-runtimes
  2. Required — runtimeconfig.json
  3. Arch — x64/x86/arm64

🔧 Still not fixed?

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