500 Internal Server Error
The application crashed while building the page. The web server is running and answered, but the code behind it threw an error it did not handle.
Where it failed: the application
What visitors see
A blank page or a generic "500" error page, on some pages or on all of them.
Usual causes
- A code error after a deploy (a missing file, a syntax error, an unhandled exception).
- The database refused or timed out (wrong credentials, too many connections, a full disk).
- A plugin, theme or package update that is incompatible with the rest.
- Wrong file permissions or a broken configuration file (.htaccess, web.config).
How to tell which one it is
- The application's error log names the line and the exception: start there.
- If only some pages fail, it is code on those pages; if every page fails, look at configuration, the database or the last deploy.
What to do
- Read the application error log (PHP: the error_log or the host's log viewer; Node, Python, Ruby: the process output or the platform's log tab).
- Roll back the last deploy or update if the error started right after it.
- WordPress: enable WP_DEBUG_LOG and disable plugins one at a time (rename the plugin's folder).
- Check the database is up and the credentials in the configuration still work.
Check the site now
The Down Checker names the layer that failed (DNS, connection, TLS or the server) and decodes the error page it gets.
Free, no sign-up. Scan only sites you own or may test. 60 scans an hour per address.