Live Server is how many people learn web development: click Go Live, and the browser reloads every time you save. When it stops working, it's usually one of these.

1. "Open with Live Server" is missing

Live Server works on a folder, not a single file. Use File → Open Folder…, open the folder that contains your index.html, then right-click the HTML file in the Explorer. If you opened just the file, the option and the Go Live button may not appear.

2. The page doesn't reload when you save

Save the file. Live reload runs on save, so with Auto Save off nothing happens until you press Ctrl+S. Turn on File → Auto Save if you like.
Your HTML needs a <body> tag. The reload script is injected into the page's body; a fragment without one can load but never reload.
You opened the file directly (file:///… in the address bar). Reloads only work on the server's address, like http://127.0.0.1:5500/index.html.

3. Port 5500 is already in use

If another Live Server, a dev server or another app holds port 5500, Live Server can't start. Close the other window, or pick a different port in your settings:

"liveServer.settings.port": 5501

Our guide to fixing "port already in use" shows how to find and stop whatever is holding the port.

4. The wrong folder is served

If your site is in a subfolder (like public or src), the server may start in the project root, and links break. Set the folder Live Server serves:

"liveServer.settings.root": "/public"

5. The browser doesn't open, or opens the wrong one

Choose the browser in settings (liveServer.settings.CustomBrowser) or open the address yourself. On Windows, also allow VS Code through the firewall the first time it asks.

6. It works on your computer but not on your phone

The server listens on your computer. Your phone must be on the same Wi-Fi, use your computer's local IP address (like http://192.168.1.20:5500) instead of 127.0.0.1, and your firewall must allow the port.

7. Changes to CSS reload the whole page

That's normal for the original extension. Some alternatives apply CSS changes instantly without a reload, which keeps your scroll position and form inputs.

8. Try a maintained alternative

The original Live Server extension hasn't been updated in years, so some issues will never be fixed. Maintained options:

Veyra Live Server: free, live reload on save, CSS changes applied without a reload, and the same Go Live button. Available for VS Code, and built into Veyra Studio.
Live Preview by Microsoft: a preview inside VS Code.
Five Server: an alternative with extras such as PHP support.

Still stuck?

Open View → Output, choose the extension in the dropdown, and read the last error. It usually names the problem: a port that's in use, a folder that doesn't exist, or a browser that couldn't start.