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JavaScript Angular Basics Setting Up an Angular Application Your First Angular Application

ng serve -o is not working

I downloaded the project files, extracted them, and then ran npm install.

Next I tried to run "ng serve -o" but I am getting this error:

The serve command requires to be run in an Angular project, but a project definition could not be found.

When I run "npm run serve", I am able to access the app from http://localhost:8080. Should this project run on a specific angular cli version?

3 Answers

Hi Aedrian

Firstly have you install angular-cli globally? make sure you cd into the project where the angular app was created then try ng serve -o

If the above doesn't work, I have had similar issues with another tool, the way I fixed this was updating to the latest version.

Hi Liam,

Thanks for the response. Yes, angular-cli is installed globally and on 7.3.3 which is the latest version. I am also running ng serve -o on the project directory (where I also ran npm run -serve and that one worked).

Hi Aedrian,

Can you check that in your project you have angular.json file and package.json file.

If you have angular-cli.json then you will need to migrate your project to the latest version

You'll find how to do this here, each project is different so fill in the information and it will give you a step by step guide on how to upgrade.

Once you've done that you will possibly need to clear your cache