Troubleshooting

When something is not working: checks and fixes.

68 guides · page 2 of 4

  • Fix 403 Forbidden in Nginx

    Nginx returns 403 Forbidden when it will not serve a file or folder. Work through the usual causes, from a missing index file to permissions, deny rules and SELinux.

    BeginnerLinux server5 min read

  • Fix 404 Not Found errors on cPanel hosting

    Find why pages return 404 Not Found on a cPanel site: wrong document root, case-sensitive file names, missing rewrite rules, moved pages, and custom error pages.

    BeginnercPanel hosting2 min read

  • Fix 502 Bad Gateway in Nginx

    A 502 Bad Gateway means Nginx could not get a valid answer from PHP-FPM or your app. Read the error log, then check the backend service, socket path, permissions and ports.

    IntermediateLinux server5 min read

  • Fix 504 Gateway Timeout in Nginx

    A 504 Gateway Timeout means PHP or your app took longer to answer than Nginx was willing to wait. Find the slow request, raise the right timeouts consistently, and fix the root cause.

    IntermediateLinux server5 min read

  • Fix a 500 Internal Server Error in WordPress

    Troubleshoot a WordPress 500 Internal Server Error on cPanel: check error logs, reset .htaccess, fix PHP settings and permissions, and isolate plugins or the theme.

    IntermediatecPanel hosting3 min read

  • Fix a 500 Internal Server Error on cPanel hosting

    Find and fix the cause of a 500 Internal Server Error on any cPanel site: broken .htaccess rules, wrong permissions, PHP version or memory problems and script errors.

    IntermediatecPanel hosting2 min read

  • Fix a Docker container that exits immediately

    Find out why a Docker container stops right after it starts. Read logs and exit codes, then fix missing environment variables, a wrong command, background processes and restart loops.

    BeginnerLinux server5 min read

  • Fix Apache failed to start (AH00072 port in use and config errors)

    When Apache will not start, run a config test, read journalctl, and fix the usual causes - AH00072 port already in use, syntax errors, missing certificates and the AH00558 ServerName warning.

    BeginnerLinux server5 min read

  • Fix AutoSSL not issuing certificates in cPanel

    Work out why cPanel AutoSSL fails for a domain: DNS not pointing here, DCV errors,.htaccess redirects, CAA records and rate limits, using the AutoSSL log in WHM.

    IntermediateLinux server4 min read

  • Fix Caddy certificate errors and ACME failures

    Diagnose why Caddy cannot get a TLS certificate. Check DNS, open ports 80 and 443, read Caddy's logs, handle Cloudflare proxying and rate limits, and test safely with the staging CA.

    IntermediateLinux server6 min read

  • Fix common Node.js errors: EADDRINUSE, 503, out of memory, module not found

    Fix the Node.js errors hosting customers see most: port already in use (EADDRINUSE), 503 on cPanel, JavaScript heap out of memory and Cannot find module.

    IntermediatecPanel hosting and Linux VPS3 min read

  • Fix common SSL errors in the browser

    Understand and fix common browser SSL errors: name mismatch, expired or untrusted certificates, incomplete chains, protocol errors and HTTPS redirect loops.

    IntermediateAll hosting3 min read

  • Fix Docker daemon not starting

    Docker service failed to start? Read the real error with journalctl, then fix an invalid daemon.json, conflicting options, storage driver and overlay errors, a full disk or iptables problems.

    IntermediateLinux server5 min read

  • Fix ERR_TOO_MANY_REDIRECTS: diagnose a redirect loop

    Trace an ERR_TOO_MANY_REDIRECTS loop across Nginx, Apache, WordPress and Cloudflare, and find the single rule that keeps sending traffic back to itself.

    IntermediateLinux server7 min read

  • Fix file upload size errors on cPanel (upload_max_filesize, 413)

    Fix 'file exceeds upload_max_filesize', 413 Request Entity Too Large and failed uploads on cPanel by raising PHP limits correctly, or using FTP for very large files.

    BeginnercPanel hosting2 min read

  • Fix MySQL or MariaDB error 1045: Access denied for user

    Error 1045 means MySQL or MariaDB rejected the login. Find which user and host the client asked for, fix the password or grants, and reset a lost root password safely.

    IntermediateLinux server6 min read

  • Fix Nginx 404 errors with try_files for pretty URLs

    Pretty URLs return 404 on Nginx when nothing routes them to your app. Add the right try_files line for WordPress, Laravel or a single-page app, and avoid root and alias mistakes.

    BeginnerLinux server4 min read

  • Fix Nginx 413 Request Entity Too Large

    Nginx returns 413 Request Entity Too Large when an upload is bigger than client_max_body_size. Raise the limit for one site or the whole server, match PHP's limits, and test.

    BeginnerLinux server5 min read

  • Fix Nginx failed to start: address already in use

    Nginx will not start when another program already holds port 80 or 443. Find what is using the port with ss, stop or move it, fix duplicate listen lines, then start Nginx.

    BeginnerLinux server5 min read

  • Fix PHP "Allowed memory size exhausted" fatal error

    PHP stops a script when it tries to allocate more memory than memory_limit allows. Find the script that hit the limit, raise the limit in the right place, and fix the cause.

    IntermediateLinux server6 min read

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