WordPress guides

Failure-mode guides for WordPress sites, organized by topic.

Crashes & Errors

8 guides

Fatal errors, white screens, memory exhaustion, and the silent failures that leave your site broken without warning.

PHP deprecation warnings after PHP 8.x upgrade — what to fix first
You upgraded WordPress to PHP 8.x. The site loads.…
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WordPress 500 internal server error — how to find the cause in logs
You open your WordPress site and the browser shows nothing but a sterile message: > 500 Internal Server Error No stack trace. No plugin name…
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WordPress fatal error — how to find what crashed your site
You hit your homepage and get a white screen, a generic "There has been a critical error on this website" message, or a hard HTTP 500. Admin…
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WordPress memory_limit exhausted — how to detect it before it crashes the site
Your WordPress admin shows a half-rendered page.…
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WordPress PHP fatal — the causal chain from warning, to update, to fatal
You're staring at a WordPress fatal you didn't cause. The site worked at 14:02; it's white-screened at 14:05.…
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WordPress PHP warning spike — finding the plugin or file causing the flood
Yesterday your PHP error log was 4 MB. This morning it is 1.2 GB and still growing. You SSH in, run du -sh /var/log/php-fpm/, and watch the …
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WordPress REST API broken after a plugin update — finding which endpoint regressed
Your WordPress block editor is a spinner. The Gutenberg sidebar shows "Updating failed. The response is not a valid JSON response." A user o…
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WordPress white screen of death — how to debug without admin access
You load your site and there is nothing. No header, no logo, no error, no 500 page. Just a flat white rectangle in the browser. View source …
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Missed schedules, dead hooks, queue workers that stop, and how to know cron is actually running.

Security

10 guides

Brute force, integrity changes, privilege escalation — attack patterns and audit signals.

WordPress "Sorry, you are not allowed to do that" — diagnosing capability check failures
Your editor is on Slack, frustrated. They opened /wp-admin/post.php?post=4912&action=edit, hit Update, and got a grey page with one line: "S…
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WordPress admin user added without your knowledge — how to detect privilege escalation
You log into /wp-admin/users.php and there it is: a WordPress admin user added without your knowledge. The username is something forgettable…
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WordPress Brute Force Attack Detection from Logs
Security plugins block attacks. But do you know how many are happening, when they spike, and which endpoints are targeted? Your logs do.…
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WordPress file integrity monitoring without a paid plugin
A core file under /wp-includes/, a plugin file under /wp-content/plugins/, or a theme functions.php is now different from the version that s…
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WordPress hundreds of new users overnight — detecting bulk spam registration before they pollute your database
You opened wp-admin/users.php this morning and the user count went from 247 to 2,113 overnight.…
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WordPress login attempt surge — distinguishing credential stuffing from scanner traffic
Your WordPress site is hammered with login attempts. The auth log is rolling. wpauthfailurestotal jumped from a flat baseline to thousands p…
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WordPress logout you didn't perform — detecting session hijacking
You were editing a post, hit Update, and WordPress bounced you to /wp-login.php with the message "Your session has expired. Please log in ag…
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WordPress REST API hammered with login attempts — how to detect credential stuffing
Your WordPress site is slow. The dashboard takes seven seconds to load. PHP-FPM workers are pinned. The Fail2Ban rule you set up two years a…
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WordPress wp-config.php was modified — how to detect unauthorized changes
You opened your WordPress site this morning and something is off. Maybe redirects to a sketchy domain. Maybe a strange admin user you do not…
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WordPress xmlrpc.php under attack — detecting amplification and credential stuffing
Your access log is suddenly full of POST /xmlrpc.php. Thousands of them. Same endpoint, hundreds of IPs, no obvious pattern in the user-agen…
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Email Delivery

4 guides

wp_mail failures, SMTP problems, contact-form leads that never arrive.

Database

7 guides

Connection errors, slow queries, deadlocks — finding the cause from logs.

WordPress "Access denied for user" database errors — credential rotation, permission grants, and silent breakage
Your WordPress site is gone.…
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WordPress "Error establishing a database connection" — detection and root cause
You open your WordPress site and the page is gone. Instead of your homepage, the browser shows a single white page with one line of text: > …
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WordPress database deadlocks — causes and detection
You open your WordPress error log after a customer complaint and see this: WordPress database error Deadlock found when trying to get lock; …
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WordPress database disk full — detecting the silent failure before queries start failing
Your WordPress site is half-broken. The homepage still loads, but WP Admin throws a white error box, comments fail to save, WooCommerce chec…
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WordPress database timeout — when no single query is slow but the request times out
A WordPress request just timed out. nginx returned 504 Gateway Timeout, the user refreshed, the page eventually loaded, and you're staring a…
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WordPress slow queries — finding the plugin or theme responsible
Your WordPress admin takes 8 seconds to render /wp-admin/edit.php. The frontend feels sluggish on category pages. Occasionally a request tim…
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WordPress slow query surge — correlating the spike with the hook that triggered it
At 14:07 your monitoring pings you because MySQL CPU jumped from 12% to 78% in a minute. By 14:09 it is back at 12%. Five minutes later it d…
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Performance

6 guides

TTFB, cache hit ratio, slow admin — performance problems that hide in plain sight.

Abuse & Scraping

5 guides

Bot traffic, scraping, enumeration — separating real users from resource-eaters.

Operations

9 guides

Plugin auto-updates, config drift, multisite isolation — operational signals you should be watching.

Logystera WordPress plugin dropping events under load — what buffer drops mean and how to fix
You opened the Logystera dashboard for one of your WordPress entities and noticed something off. The request count is suspiciously round.…
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WordPress Log Monitoring: See What Your Site Actually Does
WordPress debug.log is not monitoring. It’s a file nobody reads. Real WordPress log monitoring means structured events, derived metric…
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WordPress PHP / core version changed unexpectedly — detecting environment drift
You log into your WordPress admin, click into Tools > Site Health, and the row that used to say PHP 8.1 now says PHP 8.2. Or you ran wp core…
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WordPress plugin auto-updates that broke your site — how to detect them in time
You open your laptop at 8:47 AM and the support inbox is full. "Site is showing a white page." "Checkout is broken." "I get a 500 error on e…
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WordPress plugin silently activated or deactivated — who did it and when
You open the WordPress admin and notice something is off. A plugin you do not remember installing is active. Or a security plugin you rely o…
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WordPress Silent PHP Errors: How to Find Errors Nobody Sees
Production WordPress sites suppress error display. That’s correct. But suppressing display is not the same as handling errors. Here&rs…
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WordPress site slow for logged-in users only — detecting session floods and cache bypass
Your WordPress site is fast. Pingdom is green. The homepage TTFB is under 200ms. Then a customer support ticket comes in: "Site is unbearabl…
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WordPress upload blocked — legitimate user or attack? How to tell
A user clicks Add Media, drags a file in, and WordPress throws: > Sorry, this file type is not permitted for security reasons.…
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WordPress Uptime vs Health: Why 99.9% Uptime Means Nothing
Your uptime monitor says 99.99%. Your contact form hasn’t delivered an email in 3 weeks. Both statements are true at the same time. He…
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Monitoring for WordPress and Drupal sites. Install a plugin or module to catch silent failures — cron stalls, failed emails, login attacks, PHP errors — before users report them.
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