The 6 most common WordPress install errors: database, white screen, 404, permissions, already installed, HTTPS

A WordPress install usually goes smoothly, but sometimes you hit an error screen. The good news: nearly all of these are known, fixable problems. In this article you'll find the six most common errors that occur during a WordPress installation and a step-by-step fix for each.

The Most Common Installation Errors

The six most common WordPress install errors
The six most common errors during a WordPress install.

1) Error Establishing a Database Connection

This is the most common error and usually comes from wrong database details in wp-config.php.

Error establishing a database connection screen
The “Error establishing a database connection” screen.
  • Check the details: make sure DB_NAME, DB_USER, DB_PASSWORD and DB_HOST in wp-config.php exactly match what you created in cPanel.
  • Verify the host: on most shared hosting localhost is correct; use whatever host your provider specifies.
  • Check privileges: the user must be added to the database with ALL PRIVILEGES.
  • Reset the password: if in doubt, reset the user password in cPanel and update wp-config.php.

2) White Screen of Death

If the site shows a completely blank, white page, there's usually a PHP error, most often a plugin/theme conflict or a low PHP memory limit.

  • Enable debugging: set define('WP_DEBUG', true); in wp-config.php to see the real error.
  • Increase memory: add define('WP_MEMORY_LIMIT', '256M'); to wp-config.php.
  • Disable plugins/theme: temporarily rename the wp-content/plugins folder via FTP to turn all plugins off.

3) 404 Errors After Installation

If the homepage loads but inner pages return “404 Not Found”, the issue is with permalinks.

  • In the WordPress admin, open Settings > Permalinks and click Save Changes without changing anything. This regenerates the .htaccess rules.
  • On Apache servers, make sure .htaccess is writable and mod_rewrite is enabled.

4) File Permission / FTP Upload Errors

“Unable to write to the installation directory” or upload errors usually come from incorrect file permissions.

  • Fix permissions: folders should be 755, files 644. In your FTP client, right-click a file to set permissions.
  • Check ownership: ensure files belong to the correct user; ask hosting support if needed.
  • Don't use 777: broad permissions are a security risk and usually unnecessary.

5) “WordPress Is Already Installed” Notice

If you get an “already installed” notice when starting setup, there are leftover tables from a previous attempt in the database.

  • Go to cPanel > phpMyAdmin and delete the old WordPress tables in that database (or start fresh with a clean, empty database).
  • Creating a new database and updating wp-config.php accordingly is also a quick fix.

6) Mixed Content / HTTPS Issues

If the design breaks or a “not secure” warning appears after switching to https, the page is still loading resources over http (mixed content).

  • Update the WordPress Address and Site Address to https:// under Settings > General.
  • Update old http links in the database to https with a search-and-replace plugin.
  • Verify in cPanel that SSL is installed correctly.

A General Approach to Fixing Errors

How to approach WordPress install errors
A general troubleshooting path for install errors.

Whatever the error, follow a logical order: read the exact message, verify the wp-config.php details, check permissions, see the real error with WP_DEBUG, and if a plugin/theme is to blame, disable it and test.

Frequently Asked Questions (FAQ)

Why does the database connection error happen most?

Almost always because the database name, user, password or host in wp-config.php is wrong. Compare these four values exactly with what's in cPanel.

The white screen shows nothing — how do I find the error?

Set WP_DEBUG to true in wp-config.php to print the real PHP error; set it back to false once fixed.

All inner pages return 404 — what should I do?

Opening Settings > Permalinks and clicking Save Changes is usually enough; it regenerates the .htaccess rules.

Can I prevent these errors entirely?

Mostly yes: correct database details, correct file permissions, an up-to-date PHP version and a backup before installing prevent the majority of errors.

Conclusion

Nearly all WordPress installation errors are known, fixable problems. Verifying the database details, fixing file permissions, refreshing permalinks and revealing the real error with WP_DEBUG solves most cases. If you want to revisit the install itself, return to our WordPress installation guide.

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