Troubleshooting

Docker is not running

failed to connect to the docker API at unix:///…/docker.sock; check if the path is correct and if the daemon is running

Older Docker versions say "Cannot connect to the Docker daemon" instead. Either way, the Docker engine is not started.

1. 01

   Open Docker Desktop

   Start Docker Desktop and wait until it reports that the engine is running. On Linux, start the service: sudo systemctl start docker.
2. 02

   Check that Docker answers

   TerminalCopy

   docker info

   Expected result: It prints a Server section instead of an error.
3. 03

   Run your command again

   docker build -t agency-portfolio ., then docker run -p 3030:3030 agency-portfolio.

A port is already in use

Bind for 0.0.0.0:3030 failed: port is already allocated
ports are not available: exposing port TCP 0.0.0.0:3030 … bind: address already in use
Error: listen EADDRINUSE: address already in use :::3030

The first two lines come from docker run, the last from yarn dev or yarn start. Another program already listens on port 3030: often an earlier run of the site, or another project's dev server.

1. 01

   Find what holds the port

   On macOS or Linux:

   TerminalCopy

   lsof -i :3030

   On Windows, in PowerShell:

   TerminalCopy

   netstat -ano | findstr :3030

   An earlier container shows in docker ps.
2. 02

   Stop it

   Close that program, or stop the earlier run: Ctrl+C in its terminal, or docker stop with the container's ID. Then start the site again.
3. 03

   Or run the site on another port

   With Docker, change the number on the left of -p. The number on the right stays 3030: it is the port inside the container.

   Terminalin landing-page-template-1Copy

   docker run -p 3041:3030 agency-portfolio

   Without Docker, pass the port to the script:

   Terminalin landing-page-template-1Copy

   yarn dev -p 3041

   For a production build, yarn start -p 3041.

   Expected result: The site answers on localhost:3041Local.

The Docker build fails

The first build downloads the Node.js base image and every dependency, then builds the site. It stops with "failed to solve" and the step that failed when something gets in the way.

• No connection or a timeout: the build needs internet access. Run the command again once you are online; finished steps are cached.
• No space left on device: free space in Docker Desktop, or check what Docker uses with docker system df.
• It fails at the same step every time: build again without the cache.

docker build --no-cache -t agency-portfolio .

The folder looks different

failed to read dockerfile: open Dockerfile: no such file or directory

The command ran outside the template's folder. The ZIP holds one folder, landing-page-template-1, with the Dockerfile at its top. Some browsers unzip the download by themselves: then the folder is already in your downloads.

cd landing-page-template-1
ls

ls (or dir on Windows) lists Dockerfile, package.json, messages, public and src. Run the commands from there.

Yarn says its version is 1.22

This project's package.json defines "packageManager": "yarn@4…". However the current global version of Yarn is 1.22…

The project pins Yarn 4 through Corepack. This message means Corepack is not enabled yet, so the old global Yarn answered instead.

corepack enable

Then run yarn install again. If your Node.js has no Corepack, install it first with npm install -g corepack.

A changed setting does nothing

NEXT_PUBLIC_SITE_URL and NEXT_PUBLIC_API_BASE_URL are written into the site when it is built. A running build keeps the values it was built with.

• Without Docker: put them in .env.local in the project folder, not in .env.example. Restart yarn dev, or run yarn build again before yarn start.
• With Docker: pass them as --build-arg to docker build and build again. docker run -e does not change them.
• On Vercel or another host: change the variable, then deploy again.

• The two settings

Shared links and previews point at localhost

The canonical link, the language links or a social preview card show http://localhost:3030. The site was built without NEXT_PUBLIC_SITE_URL, which falls back to that address. Set it to your public address, such as https://www.your-domain.com, and build again.

The contact form

• It says the message was sent, but nothing arrives: NEXT_PUBLIC_API_BASE_URL is empty, so the form only shows its success message and sends nothing. Set it to your API's address and build again.
• It shows "Something went wrong. Please try again.": the request to your API's /contact path failed. The browser's developer tools show why under Network: the API is not reachable, the path does not exist, it answered with an error, or it does not accept requests from your site's address (CORS).

• The contact form

The site opens in Arabic

An address without a language, such as /, follows the browser's language, so a browser set to Arabic gets /ar. Within one browser session it also returns to the last language opened, kept in a NEXT_LOCALE cookie. Open /en for English, or use the language switch in the navbar.

The mouse pointer disappears

That is the page's own cursor: on screens 768 pixels wide and more it hides the system pointer and draws a dot and a ring instead. To keep the normal pointer, see the custom cursor.

• The custom cursor

yarn lint warns that next lint is deprecated

The warning comes from Next.js 15.5 itself. yarn lint still runs ESLint on the code and reports its results as usual.