WordPress
Diagnosing the Faults That Come Up Most
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The white screen
Almost always a PHP error, usually from a plugin or theme update, occasionally from a memory limit.
Enable error display in a staging copy, or rename the plugins folder over FTP to confirm it is a plugin. That narrows it immediately.
A slow admin area
- A plugin doing work on every admin page load
- A bloated options table from plugins that never clean up
- Too many revisions on long-lived pages
- Shared hosting under load
Slow admin and a fast front end usually means a plugin. Both slow usually means the server.
Emails not arriving
The default mail function, essentially always. Configure authenticated SMTP and the problem disappears permanently.
It is the single most expensive silent WordPress fault, because the enquiries are lost without any error.
Changes that revert
- Caching — you are seeing an old version, not a reverted one
- Editing a parent theme that gets updated
- Two people editing the same page
- A staging site being confused with live
Sudden traffic drop
| Cause | Check |
|---|---|
| Search visibility switched off | Settings, reading |
| Redirects lost in a redesign | Crawl for 404s |
| Site down intermittently | Uptime monitoring |
| A compromise | Unfamiliar files, unexpected admin users |
| Nothing on your side | Compare against a normal seasonal pattern |
Frequently asked questions
How do we tell if it is a plugin?
Deactivate all of them on a staging copy, confirm the problem is gone, reactivate one at a time. Slow and definitive.
What if we cannot access the admin?
Rename the plugins folder over FTP or file manager. That deactivates them all and usually restores access.
Should we increase the memory limit?
It fixes some errors and it is a symptom rather than a cause. Find out what is consuming it.
When should we call someone?
When the site is down and you have tried the obvious. Time spent guessing during downtime costs more than an hour of help.
Site behaving strangely?
Most WordPress faults have a small number of usual causes. Tell us the symptom.