Unpackage a WinUI 3 app

In your .csproj file, find the first existing PropertyGroup element, which also contains OutputType, TargetFramework, and other properties.

• Add the WindowsPackageType project property to this PropertyGroup element. Set its value to None.

<Project ...>
  ...
  <PropertyGroup>
    <WindowsPackageType>None</WindowsPackageType><!-- add this -->
    <OutputType>WinExe</OutputType>
    <TargetFramework>net8.0-windows10.0.19041.0</TargetFramework>
    ...
  </PropertyGroup> 
  ...
</Project>

To start the app from Visual Studio (either Debugging or Without Debugging), select the Unpackaged launch profile from the Start drop-down. If the Package profile is selected, then you'll see a deployment error in Visual Studio. This step isn't necessary if you start the application (.exe) from the command line or from Windows File Explorer.

In your .vcxproj file, find the PropertyGroup element with Label="Globals".

• Change the value of the AppxPackage property from true to false.
• Add the WindowsPackageType project property. Set its value to None.

<Project ...>
  ...
  <PropertyGroup Label="Globals">
    ...
    <AppxPackage>false</AppxPackage><!-- update this -->
    <WindowsPackageType>None</WindowsPackageType><!-- add this -->
    ...
  </PropertyGroup> 
  ...
</Project>

The debug Start drop-down in Visual Studio changes from Local Machine to Local Windows Debugger.