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English Joomla Error Messages
Joomla gives a white screen
A white / blank screen is the most annoying error you can have, because you cannot figure out the cause of the problem when there is no error message to be seen.
So first we need to make sure that the error can be seen. This can be done in several ways.
Enable error reporting
If you have access to the administrator area of your website, go to System > General settings and go to the "Server" tab.
There you will see the option "Error reporting". Set this option to "Maximum" and view the frontend of your website to see the error message.
Enable error reporting via the configuration.php file
If the administrator area of the website also gives a white screen or you have no access due to other reasons, access the configuration.php file of the website via FTP.
Find the line starting with public $error_reporting and change it to:
public $error_reporting = 'maximum';
Look at the frontend of your website to see the error message.
You found the problem and now?
Even if you don't fully understand the error message, you can probably now see where the problem is.
Fixing an extension's error message
If you still have access to the administration screen of Joomla, you can deactivate the extension.
If you don't have access, you can deactivate the extension via FTP by changing the folder name (e.g. mod_openinghours to mod_openinghours-disabled).
Also check that there are no updates to the extension that probably already fixed the problem.
If it is not fixed, contact the extension designer.
Fix error message in Joomla
If the error is in Joomla itself, try overwriting all files with the original files.
In Joomla, get to this screen via System > Joomla > Update and check for updates. First click on check for updates and then you will see the screen below.
Even if you get to see that you have the latest version, try reinstalling the Joomla core files,
If you don't have access to the administrator area, you have to overwrite the files via FTP.
Go to downloads.joomla.org and download the latest version. Copy and overwrite all files (except the installation folder, you should not copy it again).
