How to Turn On Error Reporting & Debug in Joomla

✅ Verified on Joomla 5.4.6: the admin path and the configuration.php keys below match the live install. Turn these off again on a production site once you’re done — they can expose sensitive details.

Joomla hides PHP errors by default, which is why a fatal error often shows up as a white screen or the generic “Sorry… / 500 Whoops” page. To find the real cause, make the error visible.

Option A — From the admin (if you can reach it)

Go to System → Global Configuration → Server tab → Error Reporting and choose Maximum, then reload the broken page. The real PHP error (message, file and line) will appear.

For extra detail, also set Debug System to Yes under the System tab.

Option B — In configuration.php (if the admin is also down)

Edit configuration.php in your site root over FTP and change these two lines:

public $error_reporting = 'maximum';
public $debug = true;

Reload the page to reveal the underlying error. (On a fresh Joomla 5 install these ship as 'default' and false respectively — we verified this on Joomla 5.4.6.)

Reading what you get

“Access denied for user…” or a database message → see Could not connect to the database.
An Allowed memory size exhausted message → see PHP memory exhaustion.
A path under /components, /plugins or /templates → a faulty extension; disable it.

Important: turn it back off

On a live site, set Error Reporting back to System Default (or None) and Debug System to No when finished — leaving them on can leak server paths and details to visitors.

How to Turn On Error Reporting & Debug in Joomla

Option A — From the admin (if you can reach it)

Option B — In configuration.php (if the admin is also down)

Reading what you get

Important: turn it back off

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