Chapter 1 · about 5 minutes

Get it online

Four moves: unzip, upload, open, check. At the end of this chapter Comet is running at your own web address and has proved that your host can run it.

What you need in front of you

The Comet .zip file you downloaded.
Your hosting login — the control panel, usually called cPanel, or an FTP password. Either works.

Unzip the download

Double-click the .zip file. On Windows, right-click it and choose Extract All. You get a folder. Open it and look inside — you are checking that the download arrived whole.

There are nine things in there, and the table below is all of them. Your file manager will probably sort them alphabetically rather than in this order; what matters is that nothing is missing. If something is, the download was cut short — fetch it again rather than uploading a partial folder.

All nine items, and what each one is for
Name	What it is
`index.html`	The front door. Do not rename it.
`assets`	Comet's own code and styling.
`api`	The small server programs Comet needs. Do not rename it.
`package`	Holds `module/comet.wasm`, the program that becomes your database in chapter 3.
`guide`	This guide.
`media`	Where your uploaded pictures land later. It looks empty, and apart from one tiny placeholder file it is.
`.htaccess`	Settings for your host's web server. It may be invisible — that is normal, and it must still be uploaded.
`README.md`	A plain-text version of this chapter, for whoever opens the folder without the guide. There is nothing to do with it, and it is harmless either way — upload it or leave it behind.
`comet.config.json.example`	A worked example of the small settings file the wizard writes for you in chapter 3. It is a sample, not a form: do not copy it, rename it, or fill it in. It contains none of your details and no password.

Nothing on that list needs opening, editing or thinking about. Chapter 3 writes the one real settings file for you, and every key Comet creates is written somewhere a browser cannot read.

Do not rearrange anything

Comet works out where it lives on its own, at any depth, so you never have to configure a path. That only holds if the folder keeps its shape. Renaming api, moving package, or uploading only some of the folders will break it in ways whose error messages will not point at the cause.

Put the folder on your web host

You are copying the whole folder into public_html. Pick whichever of these two routes matches the tools you have. Both are equally correct.

Easier

Through cPanel File Manager

Sign in to your hosting control panel and open File Manager.
Go into public_html.
Optional: make a folder for the site, for example comet, and go into it.
Press Upload and upload the .zip file itself — not the unzipped folder. One file uploads far faster than several hundred.
Back in File Manager, right-click the uploaded .zip and choose Extract.
Delete the .zip afterwards to keep things tidy.

If File Manager hides .htaccess, turn on Settings → Show hidden files. Extracting from the zip handles it for you either way.

Also fine

Through FTP

Open your FTP program — FileZilla, Cyberduck, or whatever your host recommends.
Connect with the FTP details from your host.
Open public_html on the right-hand side.
Drag the unzipped folder across and wait for it to finish.
Check that hidden files were included. In FileZilla: Server → Force showing hidden files.

Set the transfer to Binary

An FTP program set to “ASCII” or “Auto” can quietly damage package/module/comet.wasm on the way up. Comet catches this later with a clear message, but it costs you a chapter. In FileZilla: Transfer → Transfer type → Binary.

Comet does not care how deep it sits. public_html/, public_html/comet/ and public_html/clients/acme/site/ all work with no settings to change.

Open the address in your browser

Type the web address of the folder you just uploaded into your browser. If you put it in public_html/comet/ on the domain example.com, that is:

https://example.com/comet/

Include the slash at the end. If your host has no certificate yet, http:// works too — Comet is built to run on plain http://.

https://example.com/comet/

Set up Comet

Step 1 of 4 · Checking your host

PHP is running

ContinueOpen the guide

Sketch of the first screen. Wording and layout will differ slightly from the version you have; the parts that matter are the heading, the host check and its badge.

Let Comet check your host

The first screen runs one test before anything else: it asks your own host whether PHP — the language Comet's server-side parts are written in — is actually running. Comet refuses to save a single password or key to disk until that test comes back clean, because on some hosts a broken setup shows visitors your files as plain text instead of running them.

You do not have to do anything. Read the badge.

What the check shows	What it means	What to do
PHP is running	Your host is fine.	Go to chapter 2.
Older PHP	PHP runs, but it is an old version. Comet works; some things are slower.	Comet offers a one-click upgrade. See below.
PHP did not run	Something is wrong with the host, not with Comet.	Something went wrong → chapter 1.

If Comet offers to switch you to a newer PHP

Say yes. It is safe by design: Comet writes the change, immediately asks your host to prove it worked, and if the proof does not come back it puts the file back exactly as it was before moving on. It will never leave you worse off than you started. If no newer version is available on your host, it tells you so and changes nothing.

Check before you move on

Your browser is showing Comet's setup screen at your own web address, and the host check is showing a green PHP is running badge.

If instead you are looking at a list of file names, a page full of code, a blank page, or an error number, go straight to Something went wrong → chapter 1 and find the entry that matches what is on your screen.

The two failures that actually happen

These are not hypothetical. Both were reproduced on a real shared host while Comet was being built, and both have a fix that takes under two minutes. Full instructions are in the troubleshooting page; here is how to recognise them.

You see code instead of a website

example.com/comet/api/probe.php

<?php /* COMET — host probe */ define('COMET_MARKER', 'COMET_PHP_OK');

Your host is handing out the contents of Comet's files instead of running them. This is the one genuinely urgent failure, because on a real site it would show strangers things meant to be private.

Fix: set the PHP version for your domain in your control panel, under MultiPHP Manager. Step by step: the raw-source entry.

A 500 error page

example.com/comet/

500 Internal Server Error

The server encountered an internal error and was unable to complete your request.

Your host rejected a line in the .htaccess settings file. Harmless, and it is one line to delete.

Fix: open .htaccess in File Manager, delete the line starting AddHandler, save, reload. Step by step: the 500 entry.