What are the best steps to take to troubleshoot a Joomla 5 500 error?

Question

Joomla 5 gets more 500 errors than the Joomla 3 version. I am getting used to seeing:

Sorry, there was a problem we could not recover from.

The server returned a "500 - Whoops, looks like something went wrong."

But error 500 doesn't give you many clues as to why there is an error or how to troubleshoot it.

I created this video walk through to help people with this issue.

https://youtu.be/tumIyXVeFaQ?si=IkyuLeda_9vMHtB4

Or if you prefer reading here are the steps

I want to create a comprehensive set of steps that I can use to try and understand the issue when troubleshooting an error 500.

Here are the things I usually try to check first: ALWAYS START BY TURNING ON JOOMLA DEBUG. It gives you the best clue.

1. PHP Version. Is it the same as your live site if working on a dev. Is it at least PHP7 if working with Joomla 5?
2. PHP Settings - although I usually don't find them to be the issue. It's worth checking them too.
3. Cache type? I usually check configuration.php to see if the cache type is "file" if it is something like Redis you could change it to file to check if Redis is the issue.

public $cache_handler = 'file';

4. Database Username/password etc. This can cause an error 500, check these settings are correct.

5. Rename .htaccess and use the default Joomla .htaccess to see if that solves the problem.

6. Edit your global configuration so that you turn on error reporting to maximum. If you can't do this via the back end, use FTP or a file manager to access configuration.php and edit this line

   public $error_reporting = 'maximum';

7. Edit your global configuration to set "system debug" to on. If you can't do this via the back end, use FTP or a file manager to access configuration.php and edit this line:

   public $debug = true;

8. Rename your templates error.php file so the default Joomla one is used in case they are not giving you enough information.

9. Check the server log files. See if you can spot a plugin or something that is interfering. Then rename that folder to check if that solves it.

10. Missing PHP module (such as mysql or mbstring). You can find them all here: https://docs.joomla.org/J4.x:Optional_Technical_Requirements. If you can't edit these in your cPanel or hosting options, you might need to use php.ini. Speak to your host to find the right method.

11. Ask your host.

12. What changed? What were you just working on? Can you change it back?

13. Turn off Gzip. Sometimes this makes things funky if error reporting is set to max on some servers.

Answer 1

I started this resource as a way to have a centralised way of updating the answer.

I then decided to create a Joomla Magazine article with fuller information (and a video).

Please note my blog is more recently updated.

https://magazine.joomla.org/all-issues/july-2024/how-to-solve-the-joomla-sorry,-there-was-a-problem-we-could-not-recover-from

I also created a blog on my own website. As the Joomla Magazine article has an approval process, and decided it was quicker for me to add additional items to my own blog.

You can find my blog here it contains the most up-to-date information https://squareballoon.co.uk/blog/tutorials/how-to-solve-the-joomla-sorry-there-was-a-problem-we-could-not-recover-from