meteor up listen tcp 0.0.0.0:80: bind: address already in use

I am using meteor up to deploy to a vps. I get the error in the title during the "Start Meteor" stage of mup deploy, along with a long list of

 Error response from daemon: endpoint (appname) not found
 Error response from daemon: No such container: (appname)-frontend

etc.

I have tried changing the imagePort value for docker in mup.js but I still get the same error, still for 0.0.0.0:80

In your case there is already an application that uses port 80. You can either remove that app and go ahead and redeploy, or you can change the port that your meteor application is going to be using, like so:

module.exports = {
  servers: { ... },
  meteor: {
    name: ...,
    path: ...
    buildOptions: ...
    env: {
      PORT: 3000,
      ROOT_URL: 'http://<your server ip>:3000',
      MONGO_URL: ...
    },

    deployCheckWaitTime: 120,
    enableUploadProgressBar: true,
  }
};