download-sdk

Downloading and Installing .NET Preview Runtimes

The WinForms repository targets .NET preview builds. Test executables and built assemblies require a matching runtime version that may not be publicly available on the official .NET download page. Use the internal CI feed URL pattern below to download and install the exact version needed.

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1 Determining the Required Version

The required runtime version can be found in multiple ways:

From an error message

When a test executable cannot find its target framework, the error includes the version:

Framework: 'Microsoft.NETCore.App', version '11.0.0-preview.4.26203.108' (x64)

From runtimeconfig.json (programmatic — preferred)

Each test executable has a .runtimeconfig.json next to it that declares the exact version required:

$rc = Get-Content "artifacts\bin\System.Windows.Forms.Tests\Debug\net11.0-windows7.0\System.Windows.Forms.Tests.runtimeconfig.json" | ConvertFrom-Json
$version = $rc.runtimeOptions.framework.version
Write-Host "Required runtime: $version"

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2 Download URL Pattern

Use the following base URL, replacing {version} with the full version string:

x64 (64-bit) — required for standard test runs

https://ci.dot.net/public/Runtime/{version}/dotnet-runtime-{version}-win-x64.msi

x86 (32-bit) — required for 32-bit test runs

https://ci.dot.net/public/Runtime/{version}/dotnet-runtime-{version}-win-x86.msi

Example

For version 11.0.0-preview.4.26203.108:

x64: https://ci.dot.net/public/Runtime/11.0.0-preview.4.26203.108/dotnet-runtime-11.0.0-preview.4.26203.108-win-x64.msi
x86: https://ci.dot.net/public/Runtime/11.0.0-preview.4.26203.108/dotnet-runtime-11.0.0-preview.4.26203.108-win-x86.msi

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3 Download and Install (PowerShell)

$version = "11.0.0-preview.4.26203.108"   # ← replace with needed version

# Download both architectures
$url64 = "https://ci.dot.net/public/Runtime/$version/dotnet-runtime-$version-win-x64.msi"
$url86 = "https://ci.dot.net/public/Runtime/$version/dotnet-runtime-$version-win-x86.msi"
$msi64 = "$env:TEMP\dotnet-runtime-$version-win-x64.msi"
$msi86 = "$env:TEMP\dotnet-runtime-$version-win-x86.msi"

Invoke-WebRequest -Uri $url64 -OutFile $msi64 -UseBasicParsing
Invoke-WebRequest -Uri $url86 -OutFile $msi86 -UseBasicParsing

# Install (requires elevation)
Start-Process msiexec.exe -ArgumentList "/i `"$msi64`" /quiet /norestart" -Wait -Verb RunAs
Start-Process msiexec.exe -ArgumentList "/i `"$msi86`" /quiet /norestart" -Wait -Verb RunAs

# Verify installation
& "C:\Program Files\dotnet\dotnet.exe" --list-runtimes | Select-String $version

# Clean up
Remove-Item $msi64, $msi86 -ErrorAction SilentlyContinue

Important: The -Verb RunAs flag triggers a UAC elevation prompt. Without it, the MSI install silently fails with exit code 1603.

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4 Verifying the Installation

After installation, verify the runtime is available:

# x64
& "C:\Program Files\dotnet\dotnet.exe" --list-runtimes | Select-String $version

# x86
& "C:\Program Files (x86)\dotnet\dotnet.exe" --list-runtimes | Select-String $version

# Or check the shared framework directory directly
Get-ChildItem "C:\Program Files\dotnet\shared\Microsoft.NETCore.App" -Filter "$($version.Split('-')[0])*"
Get-ChildItem "C:\Program Files (x86)\dotnet\shared\Microsoft.NETCore.App" -Filter "$($version.Split('-')[0])*"

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5 Fully Automated: Detect, Download, and Install

This script reads the required version from any test executable's runtimeconfig.json, downloads both architectures, and installs them:

# Auto-detect version from the first test runtimeconfig found
$rc = Get-ChildItem "artifacts\bin\*Tests*\Debug\*\*.runtimeconfig.json" |
    Select-Object -First 1
$version = (Get-Content $rc | ConvertFrom-Json).runtimeOptions.framework.version
Write-Host "Required runtime: $version"

# Check if already installed
$installed = & "C:\Program Files\dotnet\dotnet.exe" --list-runtimes 2>$null |
    Select-String ([regex]::Escape($version))
if ($installed) {
    Write-Host "Runtime $version is already installed."
    return
}

# Download
$base = "https://ci.dot.net/public/Runtime/$version"
$msi64 = "$env:TEMP\dotnet-runtime-$version-win-x64.msi"
$msi86 = "$env:TEMP\dotnet-runtime-$version-win-x86.msi"
Invoke-WebRequest "$base/dotnet-runtime-$version-win-x64.msi" -OutFile $msi64 -UseBasicParsing
Invoke-WebRequest "$base/dotnet-runtime-$version-win-x86.msi" -OutFile $msi86 -UseBasicParsing

# Install (elevated)
Start-Process msiexec.exe -ArgumentList "/i `"$msi64`" /quiet /norestart" -Wait -Verb RunAs
Start-Process msiexec.exe -ArgumentList "/i `"$msi86`" /quiet /norestart" -Wait -Verb RunAs

# Verify
& "C:\Program Files\dotnet\dotnet.exe" --list-runtimes | Select-String $version

# Clean up
Remove-Item $msi64, $msi86 -ErrorAction SilentlyContinue

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6 Alternative: Use the Repo-Local Runtime

The repository includes a local .dotnet folder (populated by .\Restore.cmd) that may already have the required runtime. To use it instead of installing system-wide:

# From the repository root:
$env:DOTNET_ROOT = "$PWD\.dotnet"
$env:PATH = "$PWD\.dotnet;$env:PATH"

Check available versions:

Get-ChildItem ".dotnet\shared\Microsoft.NETCore.App" | Select Name

Note: The repo-local runtime works for running test executables but may not be picked up by vstest.console.exe or other external tools.

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7 Troubleshooting