Debug an app that isn't part of a Visual Studio solution (C++, C#, Visual Basic, F#)
Applies to: 
Visual Studio 
Visual Studio for Mac
Note
This article applies to Visual Studio 2017. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here
You may want to debug an app (.exe file) that isn't part of a Visual Studio solution. It may be an open folder project, or you or someone else may have created the app outside of Visual Studio, or you got the app from somewhere else.
For an open folder project in Visual Studio (which has no project or solution file), see Run and debug your code or, for C++, Configure debugging parameters with launch.vs.json.
For an app that doesn't exist in Visual Studio, the usual way to debug is to start the app outside of Visual Studio, and then attach to it using Attach to Process in the Visual Studio debugger. For more information, see Attach to running processes.
Attaching to an app requires manual steps that take a few seconds. Because of this delay, attaching won't help debug a startup issue, or an app that doesn't wait for user input and finishes quickly.
In these situations, you can create a Visual Studio EXE project for the app, or import it into an existing C#, Visual Basic, or C++ solution. Not all programming languages support EXE projects.
Important
Debugging features for an app that wasn't built in Visual Studio are limited, whether you attach to the app or add it to a Visual Studio solution.
If you have the source code, the best approach is to import the code into a Visual Studio project. Then, run a debug build of the app.
If you don't have the source code, and the app doesn't have debug information in a compatible format, available debugging features are very few.
To create a new EXE project for an existing app
In Visual Studio, select File > Open > Project.
In the Open Project dialog box, select All Project Files, if not already selected, in the dropdown next to File name.
Navigate to the .exe file, select it, and select Open.
The file appears in a new, temporary Visual Studio solution.
Start debugging the app by selecting an execution command, like Start Debugging, from the Debug menu.
To import an app into an existing Visual Studio solution
With a C++, C#, or Visual Basic solution open in Visual Studio, select File > Add > Existing Project.
In the Open Project dialog box, select All Project Files, if not already selected, in the dropdown next to File name.
Navigate to the .exe file, select it, and select Open.
The file appears as a new project under the current solution.
With the new file selected, start debugging the app by selecting an execution command, like Start Debugging, from the Debug menu.