How can I disable Docker from a Visual Studio ASP.NET Web API application?

When I have created a ASP.NET Web API application, I have checked to enable Docker for the project, not really knowing what that does. Now, I cannot start my application, becasue when I run it, I have the following error:

Error   CTC1003 Visual Studio container tools require Docker to be running. 

How can I disable Docker from the project?

What you've accidentally done is added support for containerizing your web API in a Docker container. Follow this to remove that support.

1. Remove lines that look like this from your .csproj files

<DockerDefaultTargetOS>Linux</DockerDefaultTargetOS>
<DockerComposeProjectPath>..\docker-compose.dcproj</DockerComposeProjectPath>

2. Remove these files if present, from solution and physical folder where the solution is homed.
   • docker-compose.dcproj
   • dockerfile.
   • .dockerignore
   • Dockerfile.build
3. Inside your project node there should be a Properties\launchsettings.json entry. Edit this to remove the "Docker" JSON element.

Finally, close and reopen the solution to make sure there are no mistakes, rebuild, and try to run. The profile that gets run is defined in launchsettings.json and is controlled by selecting the profile on the Debug toolbar (there may be other ways).

If none of that works, I suggest deleting (after backing up) and recreating the project without checking the Docker option.