Understand wp-config.php for WordPress troubleshooting

When to use this guide

Use this reference before editing wp-config.php during a WordPress outage. Many future WordPress error paths depend on the same file: database credentials, debug logging, salts, table prefix, cache flags, and environment-specific includes.

Safety notes

• Back up wp-config.php before changing it.
• Do not share DB_PASSWORD, salts, secret keys, or private hostnames in screenshots or tickets.
• Edit the active WordPress root, not wp-config-sample.php or an old staging copy.
• Follow managed-hosting patterns if the host generates this file from panel settings or environment variables.

Basic checks

1. Confirm the file contains one active set of database constants.
2. Compare DB_NAME, DB_USER, DB_PASSWORD, and DB_HOST with the host panel or deployment secrets.
3. Check $table_prefix against the actual imported WordPress tables.
4. Look for custom includes or environment checks that override values on production.
5. If the visible error is a 500, use the debug log guide before changing unrelated settings.

Expected result

You should know whether wp-config.php is the likely failure point, whether the next step is database repair, debug logging, plugin isolation, or hosting support, and which secrets must stay redacted.

Next links

• Repair database credentials with Repair WordPress database settings in wp-config.php.
• Capture PHP failures with Enable WordPress debug log safely.
• If credentials look correct, check MySQL or MariaDB health for WordPress.