Issue with Missing DLL for MaterialDesignThemes Package (Version 5.2.1)

[ox0sara]

Issue with Missing DLL for MaterialDesignThemes Package (Version 5.2.1)

Question:

I have installed the MaterialDesignThemes NuGet package (version 5.2.1) in my WPF project, but I'm unable to locate the associated DLL files in the project directory after installation. Despite following all the necessary steps, the DLL is still missing in the bin/Debug or bin/Release directories.

Steps I have followed:

1. Installed the MaterialDesignThemes package using NuGet Package Manager Console:

   Install-Package MaterialDesignThemes -Version 5.2.1

2. Verified that the package was installed correctly via the Package Manager Console:
   The package is listed as installed:

    Install-Package MaterialDesignThemes -Version 5.2.1

3. Checked the References in Visual Studio:
   The package is listed under References in my project.

4. Checked the bin/Debug and bin/Release directories:
   No DLLs related to MaterialDesignThemes are found in either directory.

5. Cleaned and rebuilt the solution:
   Tried cleaning and rebuilding the solution multiple times with no success.

6. Checked the *.csproj file:
   Verified that the MaterialDesignThemes package is correctly referenced in the *.csproj file.

7. Checked the project.assets.json file:
   The package is listed in the project.assets.json file, but no DLLs are generated in the output folder.

Expected Behavior:
The MaterialDesignThemes.Wpf.dll file should be located in the bin/Debug or bin/Release folder after installation.

Actual Behavior:
The DLL is missing from the output directory despite following all the installation and build steps.

Environment:

• Visual Studio Version: Microsoft Visual Studio Community 2022 (64-bit) - Current
  Version 17.14.9 (July 2025)
• C# class

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Tags:

• Q&A
• MaterialDesignThemes
• Missing DLL
• WPF
• NuGet

[ox0sara]

How to Fix Missing DLL for MaterialDesignThemes Package (Version 5.2.1)

To fix the issue of missing MaterialDesignThemes.Wpf.dll in the output directory after installing the NuGet package, you need to add the following property to your .csproj file:

<CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>

Steps to Apply the Fix:

1. Open the .csproj file:

   • In Visual Studio, right-click on your project in the Solution Explorer and select "Unload Project".
   • After unloading the project, right-click it again and choose "Edit Project File".

2. Add the Property to the .csproj file:

   • Find the closing </Project> tag in your .csproj file.
   • Add the <CopyLocalLockFileAssemblies> property inside the <PropertyGroup> section (or anywhere before the closing </Project> tag).

Here’s an example of what the .csproj file should look like after adding the property:

<Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">
  <PropertyGroup>
    <OutputType>WinExe</OutputType>
    <TargetFramework>net5.0-windows</TargetFramework>
    <UseWPF>true</UseWPF>
    <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="MaterialDesignThemes" Version="5.2.1" />
  </ItemGroup>
</Project>

3. Reload the Project:

After adding the property, save the .csproj file, then right-click on the project in Solution Explorer and select "Reload Project".

4. Rebuild the Project:

Clean and rebuild the solution by selecting Build → Clean Solution and Build → Rebuild Solution in the Visual Studio menu.

Explanation:

The <CopyLocalLockFileAssemblies> property ensures that all assemblies referenced by the project (including NuGet packages like MaterialDesignThemes) are copied into the output directory (bin/Debug or bin/Release). Without this property, some assemblies might not be copied to the output folder, leading to missing DLL errors during runtime.

By adding this property, you ensure that MaterialDesignThemes.Wpf.dll is included in the build output, fixing the issue of missing DLL files.