Troubleshooting
When something is not working: checks and fixes.
127 guides · page 5 of 7
Fix the WordPress white screen of death
Fix a blank white WordPress page step by step: find the error in the logs, disable plugins and the theme from File Manager, raise memory and restore if needed.
Fix the wrong keyboard layout in Remote Desktop
Stop Remote Desktop switching to a US or wrong keyboard layout. Add your layout on the server, remove extras, set a default input method and tame Alt+Shift.
Fix WordPress permalinks and 404 errors on posts
Fix WordPress posts and pages that return 404 while the home page works: re-save permalinks, restore the .htaccess rules and check rewrite conflicts in cPanel.
Fix WordPress stuck in maintenance mode
Remove the "Briefly unavailable for scheduled maintenance" message after a failed update by deleting the .maintenance file, then finish the update safely.
Free up disk space on a Linux VPS
Find what is using space, then safely clear package caches, systemd journal logs, old Docker data and large log files without breaking running services.
FTP connection failed? Fix FileZilla and FTP login errors
Fix FTP errors such as "530 Login authentication failed", connection timeouts and "Failed to retrieve directory listing" when connecting to cPanel hosting.
High CPU or RAM usage on a Linux VPS: find the cause and fix it
Track down what is eating CPU or memory on your Linux VPS with top, ps and logs, then fix runaway PHP, MySQL, bots, Docker containers or a lack of swap.
How to fix 403 Forbidden errors in Apache
Fix Apache 403 Forbidden errors by checking Require rules, file permissions, a missing index file,.htaccess deny rules and SELinux labels, one cause at a time.
How to fix 500 Internal Server Error on Apache
Track down an Apache 500 Internal Server Error by reading error.log, then fix bad.htaccess directives, missing modules, PHP fatal errors and permission problems.
How to fix a 400 Bad Request error
A 400 Bad Request error means the server could not understand the request. Learn the common causes, from bad URLs to oversized cookies, and how to fix each one.
How to fix a 401 Unauthorized error
A 401 Unauthorized error means the page needs valid login details. Find out why it appears, how password-protected directories cause it, and how to fix it.
How to fix a 405 Method Not Allowed error
A 405 Method Not Allowed error means the server rejects the HTTP method used, such as POST or PUT. Learn the causes on hosting and how to fix forms, APIs and rewrites.
How to fix a 408 Request Timeout error
A 408 Request Timeout means the server gave up waiting for your browser to finish sending the request. Learn the causes, from slow connections to large uploads, and the fixes.
How to fix a 414 Request-URI Too Long error
A 414 Request-URI Too Long error means the URL is longer than the server accepts. Find out what creates huge URLs, such as redirect loops and long query strings, and how to fix them.
How to fix a 429 Too Many Requests error
A 429 Too Many Requests error means a rate limit was hit. Learn who applies it (server, firewall, Cloudflare or an API), and how to fix 429 errors as a visitor and as a site owner.
How to fix a 502 Bad Gateway error
A 502 Bad Gateway error means one server got an invalid reply from another behind it. Learn what causes 502 errors on hosting, CDNs and VPS servers, and how to fix them.
How to fix a 503 Service Unavailable error
A 503 Service Unavailable error means the server cannot handle the request right now. Learn how maintenance mode, resource limits, traffic spikes and stopped apps cause it.
How to fix a 504 Gateway Timeout error
A 504 Gateway Timeout means a proxy waited too long for the server behind it. Learn the causes on shared hosting, CDNs and VPS servers, and how to make slow requests finish.
How to fix Cloudflare Error 520: Web server is returning an unknown error
Cloudflare Error 520 means your origin server sent an empty, invalid or unexpected response. Learn the usual causes on hosting and how to fix error 520 step by step.
How to fix Cloudflare Error 521: Web server is down
Cloudflare Error 521 means Cloudflare could not open a connection to your origin server. Find out whether the server is down or blocking Cloudflare, and how to fix it.
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