Guides tagged “troubleshooting”
Step-by-step MdmHost guides about troubleshooting, sorted A-Z.
178 guides · page 6 of 9
Fix the WordPress login redirect loop
Fix WordPress sending you back to the login page after a correct password: cookies, site URL mismatches, HTTPS settings, caching, plugins and corrupt .htaccess rules.
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 VirtFusion WHMCS provisioning: orders that do not create servers
Troubleshoot the VirtFusion WHMCS module when paid orders fail to create a VPS: read the module log, fix tokens, IDs, capacity and OS options, and retry the create.
Fix Virtualizor WHMCS provisioning errors
Troubleshoot the Virtualizor WHMCS module when orders fail: read the module log, fix API credentials, plan and server group mapping, IP pool shortages and OS template IDs.
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.
Flush DNS cache on Windows, macOS, Linux and browsers
Clear cached DNS answers after changing records or moving hosts: commands for Windows, macOS, Linux (systemd-resolved, nscd, dnsmasq), Chrome and Firefox, and when flushing won't help.
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.
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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 "MySQL server has gone away" (error 2006)
Getting "MySQL server has gone away" during imports or long scripts? Learn the causes, from max_allowed_packet and timeouts to crashed servers, and how to fix error 2006.
How to fix "SMTP authentication failed" email errors
Your email client says SMTP authentication failed or keeps asking for a password? Learn the correct cPanel mail settings and how to fix login, port and blocked IP problems.
How to fix "Table is marked as crashed and should be repaired" in MySQL
MySQL says a table is marked as crashed and should be repaired? Learn why tables crash, how to repair them in cPanel or phpMyAdmin, and how to use mysqlcheck on a VPS.
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 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 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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- Billing & accountInvoices, renewals, the client area and your account.9 guides
- TroubleshootingWhen something is not working: checks and fixes.127 guides
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