Most Common WordPress Errors and How to Fix Them (2026)

Most WordPress errors trace back to one of four causes: a plugin or theme conflict, a low PHP memory limit, a corrupted .htaccess or wp-config.php file, or a database connection problem. Before troubleshooting any specific error, do these four things first — they resolve the majority of issues on their own: clear your cache, deactivate all plugins, switch to a default theme, and turn on WordPress debugging. The sections below cover the 12 errors site owners run into most often, with the fastest fix for each.

Before You Start Fixing Anything

Four habits apply to almost every WordPress error, regardless of what it looks like:

1. Back up your site first. Before editing core files, .htaccess, or wp-config.php, take a full backup (files + database) so you can roll back if a fix makes things worse.
2. Clear your cache — both any caching plugin you’re running and your browser cache. A surprising number of “errors” are just stale cached pages.
3. Turn on debug mode by adding define('WP_DEBUG', true); to wp-config.php. This turns a blank white screen into an actual, readable error message telling you which file and line is failing.
4. Isolate the cause by deactivating all plugins and switching to a default theme (like Twenty Twenty-Five). If the error disappears, reactivate one at a time until it comes back — that’s your culprit.

The 12 Most Common WordPress Errors

1. White Screen of Death (WSOD)

What it looks like: A completely blank page — no error message, no content, nothing.

Common causes: A PHP fatal error (often from a plugin or theme), or the site exceeding its memory limit.

Fix:

• Enable WP_DEBUG in wp-config.php to surface the actual error behind the blank screen
• Deactivate all plugins via FTP by renaming the plugins folder — if the site comes back, reactivate plugins one at a time to find the conflict
• Increase your PHP memory limit by adding define('WP_MEMORY_LIMIT', '256M'); to wp-config.php

2. 500 Internal Server Error

What it looks like: “500 Internal Server Error” or “There has been a critical error on your website” — with no further detail.

Common causes: A corrupted .htaccess file, an incompatible PHP version, a plugin/theme conflict, or exhausted memory or execution limits.

Fix:

• Rename .htaccess to .htaccess_old via FTP, then go to Settings → Permalinks → Save Changes to regenerate a fresh one — this alone resolves most 500 errors
• If that doesn’t work, deactivate plugins one by one and recheck the site after each
• Check your hosting dashboard for the PHP version in use; if it was recently changed, try reverting

3. Error Establishing a Database Connection

What it looks like: “Error establishing a database connection” instead of your site loading at all.

Common causes: Incorrect database credentials in wp-config.php, a corrupted database, or the database server being down.

Fix:

• Double-check the DB_NAME, DB_USER, DB_PASSWORD, and DB_HOST values in wp-config.php against what your host provides
• Use phpMyAdmin (via your hosting control panel) to check whether the database itself is accessible and not corrupted
• Contact your host if the database server appears to be down — this one is often outside your control

4. 404 Errors on Pages That Used to Work

What it looks like: A page that loaded fine before now returns “Page Not Found,” even though it still exists in your WordPress dashboard.

Common causes: A broken permalink structure, often after a migration, plugin update, or server change.

Fix:

• Go to Settings → Permalinks and click Save Changes without altering anything — this forces WordPress to regenerate its rewrite rules
• If that doesn’t fix it, check your .htaccess file for the standard WordPress rewrite block and restore it if missing

5. Login Page Redirect Loop

What it looks like: You enter your credentials, the page reloads, and you’re sent right back to the login screen — endlessly.

Common causes: Incorrect WP_HOME or WP_SITEURL values, corrupted cookies, or a conflicting security plugin.

Fix:

• Clear your browser cookies and cache, then try again
• Check wp-config.php for WP_HOME and WP_SITEURL — both should match your actual site URL exactly, including https://
• Temporarily deactivate security plugins via FTP (rename their folder in /wp-content/plugins/) and try logging in again

6. Syntax Error After Editing Code

What it looks like: “Parse error: syntax error, unexpected…” — usually right after editing functions.php or a snippet.

Common causes: A missing semicolon, bracket, or quote introduced during manual code edits.

Fix:

• Connect via FTP and open the file mentioned in the error message
• Undo your most recent change, or compare against a backup of the file
• If you can’t access the dashboard at all, this is the fastest fix — FTP access bypasses the broken admin entirely

7. Failed Auto-Update

What it looks like: “Briefly unavailable for scheduled maintenance” that never goes away, or a plugin/theme stuck mid-update.

Common causes: The update process was interrupted, or a .maintenance file was left behind.

Fix:

• Connect via FTP, navigate to your site’s root folder, and delete the .maintenance file
• Manually update the affected plugin or theme: download the current version from WordPress.org, then go to Plugins → Add New → Upload Plugin and replace the existing version

8. Images Not Uploading / Media Upload Errors

What it looks like: “HTTP Error” when uploading an image, or uploads that hang indefinitely.

Common causes: Incorrect file/folder permissions, insufficient PHP memory, or exceeding the server’s upload size limit.

Fix:

• Check that the /wp-content/uploads/ folder has the correct permissions (typically 755 for folders, 644 for files) via FTP
• Increase upload_max_filesize and post_max_size in your PHP settings, if your host allows it
• Try a different image format or a smaller file size to rule out a size-limit issue

9. Mixed Content / SSL Warnings

What it looks like: A browser padlock warning, or “Your connection is not fully secure,” even though you have an SSL certificate installed.

Common causes: Some page resources (images, scripts) are still being loaded over http:// instead of https://.

Fix:

• Update your site URL under Settings → General to use https://
• Use a plugin like Really Simple SSL, or manually search your database for hardcoded http:// references and update them
• Clear any caching layer (including CDN-level caching) after making the change

10. Emails Not Sending (Password Resets, Contact Forms, WooCommerce Orders)

What it looks like: Password reset emails, form notifications, or order confirmations never arrive.

Common causes: WordPress’s default mail() function is frequently restricted or blocked outright by hosting providers due to spam abuse.

Fix:

• Install an SMTP plugin (WP Mail SMTP is the most widely used) and connect it to a dedicated transactional email service like SendGrid, Mailgun, or Amazon SES
• These services offer reliable delivery and bounce tracking that the default PHP mail function simply doesn’t provide

11. “Briefly Unavailable for Scheduled Maintenance” (Stuck)

What it looks like: This message persists long after an update should have finished.

Common causes: Same root cause as the failed auto-update above — an interrupted update process leaving a leftover maintenance flag.

Fix: Delete the .maintenance file from your site’s root directory via FTP, as described in error #7.

12. REST API / Block Editor Errors (“The editor has encountered an unexpected error”)

What it looks like: The block editor (Gutenberg) fails to load, or you see REST API-related error messages when trying to save a post.

Common causes: A plugin conflict, a security plugin or firewall blocking REST API requests, or a permalink issue.

Fix:

• Deactivate plugins one by one to isolate the conflict, paying particular attention to security and firewall plugins
• Re-save your permalinks under Settings → Permalinks
• Check whether your host or a security plugin is blocking /wp-json/ REST API requests, and allow them if so

Quick Reference Table

When to Call in a Developer

Most of the errors above are fixable without coding experience, provided you’re comfortable using FTP and editing a couple of lines in wp-config.php. That said, bring in a developer or your host’s support team if:

• The error persists after ruling out plugins, theme, and .htaccess
• You’re not comfortable editing core files or your database directly
• The site handles sensitive data (payments, user accounts) and downtime carries real business risk

Frequently Asked Questions

Why does my WordPress site keep breaking after updates? Most post-update breakage comes from a plugin or theme that hasn’t been updated to match the new WordPress or PHP version. Testing updates on a staging site before applying them to production is the most reliable way to avoid this.

Is it safe to edit wp-config.php myself? Yes, as long as you back up the file first and edit it via FTP or your host’s file manager. A single missing character can cause a fatal error, so always keep the original file to restore from.

What’s the very first thing I should try for any WordPress error? Clear your cache and deactivate all plugins. Between those two steps, a large share of WordPress errors resolve immediately, pointing you straight at the plugin conflict responsible.

Can a WordPress error cause permanent data loss? Rarely, on its own — most of these errors affect how the site displays or functions, not the underlying database. Still, always maintain regular backups so a bad update or edit is never a one-way door.

Do these fixes work the same way on managed WordPress hosting? Mostly, though some managed hosts restrict direct file editing or handle caching and SSL at the server level. Check your host’s documentation for anything that differs from the general fixes above — namely .htaccess access and PHP configuration changes.