# Troubleshooting

## A page looks broken after enabling a setting

1. Click **Clear Cache** and reload the page — a stale cached copy from before your change is the most common cause.
2. If it's still wrong, identify the most recently changed setting and turn it off, then clear the cache again to confirm that was the cause.
3. Check the notes below for the settings most likely to cause a visible issue.

## Settings most likely to need attention if something looks wrong

| Setting | Tab | What to check |
|---|---|---|
| **Load Combined CSS Asynchronously** | CSS | Causing a flash of unstyled content? You need Critical CSS filled in — see [CSS Optimisation](css-optimisation.md). |
| **Combine JavaScript Files** / **Delay JavaScript Until User Interaction** | JavaScript | A feature stopped working? Find its script's handle or filename in your browser's developer tools and add it to the exclude field. |
| **Disable WooCommerce Scripts on Non-Shop Pages** | Advanced | My Account page (orders, downloads) look unstyled? This is the setting — check it isn't excluding those pages incorrectly for your theme. |
| **Cache Pages for Logged-in Users** | Caching | Seeing content meant only for logged-in users appear for anonymous visitors? Turn this off and clear the cache. |
| **WordPress Heartbeat: Disable** | Advanced | Autosave or "someone else is editing this" notices stopped working? Switch back to Optimise instead of Disable. |

## "Add define('WP_CACHE', true) to your wp-config.php" notice won't go away

The plugin tries to add this automatically when activated. If your hosting doesn't allow it to write to `wp-config.php`, you'll see this notice with a **Retry automatically** button. If retrying doesn't clear it, add the line yourself:

```php
define( 'WP_CACHE', true );
```

Place it above the `/* That's all, stop editing! */` line near the bottom of `wp-config.php`. Your site caches correctly either way — this notice is about reaching the *fastest* of three delivery methods, not about caching being broken.

## Cache directory not writable

If you see a notice that `wp-content/cache/` isn't writable, your hosting needs that directory (and the plugin's subfolder within it) set to permission 755. Most hosts allow this by default; shared hosting with unusually strict permissions occasionally needs it set manually via your file manager or hosting support.

## A specific plugin or theme feature stopped working

Most compatibility issues trace back to combined CSS/JS. Add the affected stylesheet or script to the **Exclude Handles or Filenames** field on the relevant tab ([CSS](css-optimisation.md) or [JavaScript](javascript-optimisation.md)) rather than turning combining off entirely — this keeps the optimisation for everything else while carving out the one exception you need.

## Before uninstalling

Clear your cache manually first, and if you've been using the automatic `WP_CACHE` setup, you may want to remove `define( 'WP_CACHE', true );` from `wp-config.php` yourself afterward — uninstalling the plugin doesn't automatically remove that line.