NET 5.0 self-contained single-file winforms application crashes while accessing settings

[t081as]

Description

A .NET 5.0 self-contained application crashes while accessing application settings from a .settings file.

Reproduction

Create a new winforms project (net5.0-windows)

> dotnet new winforms

Open the project in Visual Studio and add a "Settings file" (e.g. "Settings1.settings")
Add the setting:

Name: Test
Type: string
Scope: User
Value: Hello

Update the Main method (Program.cs) to read the value:

using System;
using System.Windows.Forms;

namespace SettingsIssue
{
    static class Program
    {
        /// <summary>
        ///  The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.SetHighDpiMode(HighDpiMode.SystemAware);
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);

            string myValue = Settings1.Default.Test;

            Application.Run(new Form1());
        }
    }
}

Add single file publish options to the csproj file:

<!-- ... -->
<PublishSingleFile>true</PublishSingleFile>
<RuntimeIdentifier>win-x64</RuntimeIdentifier>
<!-- ... -->

Publish the application (self-contained) and run it.

> dotnet publish --self-contained

Expected behavior:
The form is shown.

Actual behavior:
No form is shown; the windows event log contains the following exception:

Application: SettingsIssue.exe
CoreCLR Version: 5.0.20.51904
.NET Version: 5.0.0
Description: The process was terminated due to an unhandled exception.
Exception Info: System.IO.FileNotFoundException: Das System kann die angegebene Datei nicht finden. (0x80070002)
   at System.Reflection.RuntimeModule.GetFullyQualifiedName()
   at System.Reflection.RuntimeModule.get_Name()
   at System.Configuration.ClientConfigPaths..ctor(String exePath, Boolean includeUserConfig)
   at System.Configuration.ClientConfigPaths.GetPaths(String exePath, Boolean includeUserConfig)
   at System.Configuration.Internal.ConfigurationManagerInternal.System.Configuration.Internal.IConfigurationManagerInternal.get_ExeProductName()
   at System.Configuration.ApplicationSettingsBase.get_Initializer()
   at System.Configuration.ApplicationSettingsBase.CreateSetting(PropertyInfo propertyInfo)
   at System.Configuration.ApplicationSettingsBase.EnsureInitialized()
   at System.Configuration.ApplicationSettingsBase.get_Properties()
   at System.Configuration.SettingsBase.GetPropertyValueByName(String propertyName)
   at System.Configuration.SettingsBase.get_Item(String propertyName)
   at System.Configuration.ApplicationSettingsBase.GetPropertyValue(String propertyName)
   at System.Configuration.ApplicationSettingsBase.get_Item(String propertyName)
   at SettingsIssue.Settings1.get_Test()
   at SettingsIssue.Program.Main()

Configuration

.NET SDK (gemäß "global.json"):
Version: 5.0.100
Commit: 5044b93829

Laufzeitumgebung:
OS Name: Windows
OS Version: 10.0.19041
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\5.0.100\

Host (useful for support):
Version: 5.0.0
Commit: cf258a1

.NET SDKs installed:
5.0.100 [C:\Program Files\dotnet\sdk]

Tagging subscribers to this area: @agocke, @vitek-karas
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Details

---

Issue meta data

Issue content:
	### Description A .NET 5.0 self-contained application crashes while accessing application settings from a .settings file. Reproduction Create a new winforms project (net5.0-windows) > dotnet new winforms Open the project in Visual Studio and add a "Settings file" (e.g. "Settings1.settings") Add the setting: Name: Test Type: string Scope: User Value: Hello Update the Main method (Program.cs) to read the value: using System; using System.Windows.Forms; namespace SettingsIssue { static class Program { /// <summary> /// The main entry point for the application. /// </summary> [STAThread] static void Main() { Application.SetHighDpiMode(HighDpiMode.SystemAware); Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); string myValue = Settings1.Default.Test; Application.Run(new Form1()); } } } Add single file publish options to the csproj file: <!-- ... --> <PublishSingleFile>true</PublishSingleFile> <RuntimeIdentifier>win-x64</RuntimeIdentifier> <!-- ... --> Publish the application (self-contained) and run it. > dotnet publish --self-contained Expected behavior: The form is shown. Actual behavior: No form is shown; the windows event log contains the following exception: Application: SettingsIssue.exe CoreCLR Version: 5.0.20.51904 .NET Version: 5.0.0 Description: The process was terminated due to an unhandled exception. Exception Info: System.IO.FileNotFoundException: Das System kann die angegebene Datei nicht finden. (0x80070002) at System.Reflection.RuntimeModule.GetFullyQualifiedName() at System.Reflection.RuntimeModule.get_Name() at System.Configuration.ClientConfigPaths..ctor(String exePath, Boolean includeUserConfig) at System.Configuration.ClientConfigPaths.GetPaths(String exePath, Boolean includeUserConfig) at System.Configuration.Internal.ConfigurationManagerInternal.System.Configuration.Internal.IConfigurationManagerInternal.get_ExeProductName() at System.Configuration.ApplicationSettingsBase.get_Initializer() at System.Configuration.ApplicationSettingsBase.CreateSetting(PropertyInfo propertyInfo) at System.Configuration.ApplicationSettingsBase.EnsureInitialized() at System.Configuration.ApplicationSettingsBase.get_Properties() at System.Configuration.SettingsBase.GetPropertyValueByName(String propertyName) at System.Configuration.SettingsBase.get_Item(String propertyName) at System.Configuration.ApplicationSettingsBase.GetPropertyValue(String propertyName) at System.Configuration.ApplicationSettingsBase.get_Item(String propertyName) at SettingsIssue.Settings1.get_Test() at SettingsIssue.Program.Main() Configuration .NET SDK (gemäß "global.json"): Version: 5.0.100 Commit: 5044b93829 Laufzeitumgebung: OS Name: Windows OS Version: 10.0.19041 OS Platform: Windows RID: win10-x64 Base Path: C:\Program Files\dotnet\sdk\5.0.100\ Host (useful for support): Version: 5.0.0 Commit: cf258a1 .NET SDKs installed: 5.0.100 [C:\Program Files\dotnet\sdk] </td>
Issue author:		t081as
Assignees:	-
Labels:	`area-Single-File`, `untriaged` </td>
Milestone:	-

[vitek-karas]

This is a duplicate of #42176. That has been fixed in 6.0, but hasn't been ported to 5.0.

A workaround is to set <IncludeAllContentForSelfExtract>true</IncludeAllContentForSelfExtract>. See https://github.com/dotnet/designs/blob/main/accepted/2020/single-file/design.md#optional-settings for details on what that does.