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+---
+description: 'Guidelines for working with .NET Framework projects'
+applyTo: '**/*.csproj', '**/*.cs'
+description: 'These instructions provide guidance  for working with .NET Framework projects. Because .NET Framework projects require different tools and language versions compared to .NET/.NET Core, these instructions can be
+helpful for ensuring LLMs understand the context and requirements of .NET Framework development.'
+---
+
+# .NET Framework Development
+
+## Build and Compilation Requirements
+- Always use `msbuild /t:rebuild` to build the solution or projects instead of `dotnet build`
+
+## C# Language Version is 7.3
+- This project is limited to C# 7.3 features only. Please avoid using:
+  - C# 8.0+ features like using declarations (using var x = ...)
+  - await using statements
+  - Switch expressions
+  - etc.
+
+## Project File Management
+- All new source files **MUST** be explicitly added to the project file (`.csproj`) using a `<Compile>` element
+  - .NET Framework projects do not automatically include files in the directory like SDK-style projects
+  - Example: `<Compile Include="Path\To\NewFile.cs" />`
+
+## NuGet Package Management
+- Instead, ask the user to install or update NuGet packages using the Visual Studio NuGet Package Manager or Visual Studio package manager console.
+- Installing and updating NuGet packages in .NET Framework projects is a complex task requiring coordinated changes to multiple files. Therefore, **do not attempt to install or update NuGet packages** in this project.
+- When recommending NuGet packages, ensure they are compatible with .NET Framework or .NET Standard 2.0 (not only .NET Core or .NET 5+).
+
+## Environment Considerations (Windows environment)
+- Use Windows-style paths with backslashes (e.g., `C:\path\to\file.cs`)
+- Use Windows-appropriate commands when suggesting terminal operations
+- Consider Windows-specific behaviors when working with file system operations