Strkyer wont run with No project references found. on testproject with references to multiple projects

[TimThaler]

This is already discussed here and here.
I am trying to use stryker with one of our test projects in C#. This projects references many other source-projects (not just the one testing) and even another test project. I think this is

When running stryker with dotnet stryker -L is gives me : No project references found. Please add a project reference to your test project and retry.
The directry where i issue the command dotnet stryker contains the Project.Test.csproj-File, e.g. the test project directry is the working directory. The referenced solution file lives two levels up.
Below i pasted stryker config file, parts of the csproj file of the testproject, and the log output.

The console output is:

[15:02:57 DBG] Stryker starting, version: 4.8.0

[15:02:57 VRB]   CACHE https://api.nuget.org/v3/registration5-gz-semver2/dotnet-stryker/index.json
A new version of Stryker.NET (4.8.1) is available. Please consider upgrading using `dotnet tool update -g dotnet-stryker`

[15:02:57 DBG] Stryker started with options: {"MsBuildPath": null, "DevMode": false, "ProjectPath": "C:\\path\\Test\\Project.Test", "IsSolutionContext": false, "WorkingDirectory": "C:\\path\\Test\\Project.Test", "OutputPath": "C:\\path\\Test\\Project.Test\\StrykerOutput\\2025-09-24.15-02-57", "ReportPath": "C:\\path\\Test\\Project.Test\\StrykerOutput\\2025-09-24.15-02-57\\reports", "ReportFileName": "mutation-report", "SolutionPath": "C:\\path\\MainSolution.sln", "Configuration": null, "TargetFramework": null, "LogOptions": {"LogToFile": false, "LogLevel": "Verbose", "$type": "LogOptions"}, "MutationLevel": "Advanced", "Thresholds": {"High": 80, "Low": 60, "Break": 0, "$type": "Thresholds"}, "AdditionalTimeout": 5000, "LanguageVersion": "CSharp7_3", "Concurrency": 8, "SourceProjectName": "Project.csproj", "TestProjects": [], "TestCaseFilter": "", "Reporters": ["Progress", "Html"], "WithBaseline": false, "BaselineProvider": "Disk", "AzureFileStorageUrl": "", "AzureFileStorageSas": "", "DashboardUrl": "https://dashboard.stryker-mutator.io", "DashboardApiKey": null, "Since": false, "SinceTarget": "master", "DiffIgnoreChanges": [], "FallbackVersion": "master", "ModuleName": "", "ReportTypeToOpen": null, "Mutate": [{"Glob": {"Tokens": [{"TrailingPathSeparator": {"Value": "\\", "$type": "PathSeparatorToken"}, "LeadingPathSeparator": null, "$type": "WildcardDirectoryToken"}, {"$type": "WildcardToken"}], "$type": "Glob"}, "IsExclude": false, "TextSpans": [{"Start": 0, "End": 2147483647, "Length": 2147483647, "IsEmpty": false, "$type": "TextSpan"}], "$type": "FilePattern"}], "IgnoredMethods": [], "ExcludedMutations": [], "ExcludedLinqExpressions": [], "OptimizationMode": "CoverageBasedTest", "ProjectName": "", "ProjectVersion": "", "BreakOnInitialTestFailure": false, "MutantIdProvider": {"$type": "BasicIdProvider"}, "$type": "StrykerOptions"}
[15:02:57 INF] Analysis starting.
[15:02:57 VRB] Scanned the directory C:\path\Test\Project.Test for *.csproj files: found ["C:\\path\\Test\\Project.Test\\Project.Test.csproj"]
[15:02:57 VRB] Found project file C:\path\Test\Project.Test\Project.Test.csproj in path C:\path\Test\Project.Test
[15:02:57 DBG] Using C:\path\Test\Project.Test\Project.Test.csproj as test project
[15:02:57 INF] Analyzing 1 test project(s).
[15:02:57 DBG] Analyzing 30 projects.
[15:02:57 DBG] Analyzing Project.Test.csproj
[15:03:05 DBG] Analysis of project Project.Test.csproj succeeded.
[15:03:05 INF] Analysis complete.
[15:03:05 INF] Time Elapsed 00:00:08.0652392
Stryker.NET failed to mutate your project. For more information see the logs below:


No project references found. Please add a project reference to your test project and retry.

The log file contains this: (the timestamps missmatch but the output is identical)

2025-09-24T14:21:13.6843937+02:00  [INF] Logging enabled at level Trace (8a18af78)
2025-09-24T14:21:13.7001249+02:00  [DBG] Stryker starting, version: "4.8.0" (e60f399b)
2025-09-24T14:21:14.0479904+02:00  [DBG] Stryker started with options: StrykerOptions { MsBuildPath: null, DevMode: False, ProjectPath: "C:\pathToProject\Test\Project.Test", IsSolutionContext: False, WorkingDirectory: "C:\pathToProject\Test\Project.Test", OutputPath: "C:\pathToProject\Test\Project.Test\StrykerOutput\2025-09-24.14-21-13", ReportPath: "C:\pathToProject\Test\Project.Test\StrykerOutput\2025-09-24.14-21-13\reports", ReportFileName: "mutation-report", SolutionPath: "C:\pathToProject\MainSolution.sln", Configuration: null, TargetFramework: null, LogOptions: LogOptions { LogToFile: True, LogLevel: Verbose }, MutationLevel: Standard, Thresholds: Thresholds { High: 80, Low: 60, Break: 0 }, AdditionalTimeout: 5000, LanguageVersion: CSharp7_3, Concurrency: 8, SourceProjectName: "Project", TestProjects: [], TestCaseFilter: "", Reporters: [Progress, Html], WithBaseline: False, BaselineProvider: Disk, AzureFileStorageUrl: "", AzureFileStorageSas: "", DashboardUrl: "https://dashboard.stryker-mutator.io", DashboardApiKey: null, Since: False, SinceTarget: "master", DiffIgnoreChanges: [], FallbackVersion: "master", ModuleName: "", ReportTypeToOpen: null, Mutate: [FilePattern { Glob: Glob { Tokens: [WildcardDirectoryToken { TrailingPathSeparator: PathSeparatorToken { Value: \ }, LeadingPathSeparator: null }, WildcardToken {  }] }, IsExclude: False, TextSpans: [TextSpan { Start: 0, End: 2147483647, Length: 2147483647, IsEmpty: False }] }], IgnoredMethods: [], ExcludedMutations: [], ExcludedLinqExpressions: [], OptimizationMode: CoverageBasedTest, ProjectName: "", ProjectVersion: "", BreakOnInitialTestFailure: False, MutantIdProvider: BasicIdProvider {  } } (fac41b16)
2025-09-24T14:21:14.1169402+02:00  [INF] Analysis starting. (7076a364)
2025-09-24T14:21:14.2271486+02:00  [DBG] Using "C:\pathToProject\Test\Project.Test\Project.Test.csproj" as test project (00c34121)
2025-09-24T14:21:14.2292007+02:00  [INF] Analyzing 1 test project(s). (7a597dff)
2025-09-24T14:21:14.2311811+02:00  [DBG] Analyzing 30 projects. (a101d45b)
2025-09-24T14:21:14.2545032+02:00  [DBG] Analyzing "Project.Test.csproj" (55dfba44)
2025-09-24T14:21:19.5499089+02:00  [DBG] Analysis of project "Project.Test.csproj" succeeded. (adaf2e80)
2025-09-24T14:21:19.5566793+02:00  [INF] Analysis complete. (f039f576)
2025-09-24T14:21:19.5583033+02:00  [INF] Time Elapsed 00:00:05.6238428 (f4427d77)

The .csproj-File:

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="15.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <Import Project="..\..\packages\AnotherProject.props" Condition="Exists('..\..\packages\AnotherProject\build\AnotherProject.props')" />
  <Import Project="..\..\packages\NUnit.3.13.1\build\NUnit.props" Condition="Exists('..\..\packages\NUnit.3.13.1\build\NUnit.props')" />
  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
  <PropertyGroup>
    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
    <ProjectGuid>id</ProjectGuid>
    <OutputType>Library</OutputType>
    <AppDesignerFolder>Properties</AppDesignerFolder>
    <RootNamespace>Project.Test</RootNamespace>
    <AssemblyName>Project.Test</AssemblyName>
    <TargetFrameworkVersion>v4.8</TargetFrameworkVersion>
    <FileAlignment>512</FileAlignment>
    <NuGetPackageImportStamp>
    </NuGetPackageImportStamp>
    <TargetFrameworkProfile />
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
    <DebugSymbols>true</DebugSymbols>
    <DebugType>full</DebugType>
    <Optimize>false</Optimize>
    <OutputPath>..\..\out\</OutputPath>
    <DefineConstants>DEBUG;TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
    <PlatformTarget>x86</PlatformTarget>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
    <DebugType>pdbonly</DebugType>
    <Optimize>true</Optimize>
    <OutputPath>..\..\out\</OutputPath>
    <DefineConstants>TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
    <PlatformTarget>x86</PlatformTarget>
  </PropertyGroup>
  <ItemGroup>
    <Reference Include="System.Web" />
    ... standard nuget packages ...
  </ItemGroup>
  <ItemGroup>
    <Compile Include="....cs" />
   ...
  </ItemGroup>
  <ItemGroup>
    <ProjectReference Include="..\..\Src\AnotherSourceProjectWhichIsNeeded.csproj">
      <Project>{...}</Project>
      <Name>...</Name>
    </ProjectReference>
    <ProjectReference Include="..\..\Test\ATestProjectWhichIsNeeded.Tests.csproj">
      <Project>{...}</Project>
      <Name>...</Name>
    </ProjectReference>
    <ProjectReference Include="..\..\Src\YetAnotherSourceProjectWhichIsNeeded1.csproj">
      <Project>{...}</Project>
      <Name>...</Name>
    </ProjectReference>
    <ProjectReference Include="..\..\Src\YetAnotherSourceProjectWhichIsNeeded2.csproj">
      <Project>{...}</Project>
      <Name>...</Name>
    </ProjectReference>
    <ProjectReference Include="..\..\Src\YetAnotherSourceProjectWhichIsNeeded3.csproj">
      <Project>{...}</Project>
      <Name>...</Name>
    </ProjectReference>
    <ProjectReference Include="..\..\Src\Project.csproj">  -> The project this testproject covers
      <Project>{...}</Project>
      <Name>Project</Name>
    </ProjectReference>
    <ProjectReference Include="..\..\Src\YetAnotherSourceProjectWhichIsNeeded4.csproj">
      <Project>{...}</Project>
      <Name>...</Name>
    </ProjectReference>
  </ItemGroup>
  <ItemGroup>
    <None Include="app.config" />
    <None Include="packages.config" />
  </ItemGroup>
  <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
    <PropertyGroup>
      <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
    </PropertyGroup>
    <Error Condition="!Exists('..\..\packages\NUnit.3.13.1\build\NUnit.props')" Text="$([System.String]::Format('$(ErrorText)', '..\..\packages\NUnit.3.13.1\build\NUnit.props'))" />
  </Target>
</Project>

Stryker Setup:

{
  "stryker-config": {
	  "solution": "../../MainSolution.sln",
      "project": "Project.csproj",
      "language-version": "Csharp7_3",
      "verbosity": "trace",
      "mutation-level": "Advanced"
  }
}

[TimThaler]

Some things i can assure:

• stryker config: "project": "Project.csproj", It is the project name without typo. It is not a path.
• dotnet list Project.Test.csproj reference shows that a reference to the original project is set
• changing the platform target to AnyCPU gives me the same result

[TimThaler]

Update: I narrowed it down by removing all non-standard references (meaning all nuget installed or system packages are referenced) There is only the reference to the project under test. But i still get the error message

[dupdob]

try running Stryker with --dev-mode option, it will provide more details related to project analysis.
It is possible Stryker silentrly fails to analyze Project.csproj.