The five things that most often look like a fault and are not. Before assuming something is broken, look here.

1. I created the menu and the site looks the same

The module is missing. In Joomla a menu is not drawn just because it exists: it needs a Menu module pointing at it, published in a position. That is Content → Site Modules → New → Menu. The wizard creates it for you; if you built the menu by hand, this is what is missing.

2. A section comes up empty

Almost always the access level: a visitor only sees what is set to “Public”. Check it on the gallery, on the event category or on the document itself — not on the screen that lists them.

The calendar has another cause: it only shows upcoming events. With past dates it looks empty even though the events are there.

3. I pasted a design in and it vanished

Joomla strips certain tags —among them <style> and <svg>— from anything saved in an article or a module. It is on its default blocklist and it does not warn you. Change it in System → Global Configuration → Text Filters.

4. It looks different on my computer and on my phone

The phone wins, especially the first time it visits. On the computer, reload with Ctrl+F5. Style files carry a version number that only changes when an extension is installed or updated; until then the browser reuses the copy it already fetched.

5. Odd text like COM_MAGON_SOMETHING shows up

That is a missing language label. It breaks nothing, but do tell us: it gets fixed in the next release.

If none of this fits

Take a screenshot of the whole screen, address bar included, and send it. It settles in a minute what takes three emails to describe.