Fix the WordPress White Screen of Death / HTTP 500

A blank white page or HTTP 500 error with no message is called the "White Screen of Death" (WSOD). It's frustrating because WordPress shows nothing to help you diagnose the problem. Fortunately, there are systematic steps to identify and fix it.

Step 1: Enable Debug Mode

The first step is to turn on WordPress debugging so you can see the actual error message.

1. Open wp-config.php via FTP or your control panel's File Manager (it's in your site's root directory).
2. Find these lines:
```php
define( 'WP_DEBUG', false );
```
3. Change them to:
```php
define( 'WP_DEBUG', true );
define( 'WPDEBUGLOG', true );
define( 'WPDEBUGDISPLAY', false );
```
4. Save the file.
5. Visit your site in a browser. The white screen should still appear (because display is off), but WordPress is now logging errors.
6. Download your site's debug log:
- Via FTP or File Manager, navigate to /wp-content/debug.log.
- Right-click and download it, or open it to view the errors.
7. Look at the errors and note the most recent ones—they'll give you clues about what's breaking.

Step 2: Check for Plugin or Theme Conflicts

A faulty plugin or theme is the most common cause of the white screen.

1. Disable all plugins temporarily:
- Via FTP or File Manager, navigate to /wp-content/.
- Rename the plugins folder to plugins-disabled.
- Visit your site—if it works now, a plugin is the culprit.
- Rename the folder back to plugins.
2. Enable plugins one by one:
- In WordPress, go to Plugins and activate each plugin individually.
- After activating each one, visit your site to see if the error returns.
- When the error appears, you've found the bad plugin—delete it or update it.
3. If disabling plugins didn't help, test your theme:
- In WordPress, go to Appearance > Themes.
- Switch to a default WordPress theme (Twenty Twenty-Three or similar).
- If the error goes away, your active theme is the problem.
- Contact the theme developer for an update, or switch to a different theme.

Step 3: Increase PHP Memory Limit

WordPress and plugins need memory to run. If your server's memory limit is too low, operations fail.

1. Check your debug log (from Step 1) for "fatal" errors mentioning "allowed memory size"—this confirms the problem.
2. If that's the issue, increase the memory limit:
- Open wp-config.php again.
- Add this line before "That's all, stop editing!":
```php
define( 'WPMEMORYLIMIT', '256M' );
```
- Save and refresh your site.
3. If that doesn't work, try 512M or ask your hosting provider about increasing your server's memory allocation.

Step 4: Check PHP Version and Extensions

Some plugins require a newer PHP version or specific extensions.

1. In your control panel, find "PHP" or "Software" section.
2. Check your current PHP version and which extensions are installed.
3. If you're running an old version (PHP 7.2 or older):
- Contact your host to upgrade to PHP 8.0+.
- Some plugins won't work on very old PHP versions.
4. Check the debug log for errors mentioning missing extensions like "mbstring" or "curl"—contact your host to enable them.

Step 5: Check Your .htaccess File

A corrupted .htaccess file (which controls URL rewriting) can cause a 500 error.

1. Via FTP or File Manager, navigate to your site's root (usually public_html).
2. Look for .htaccess (it's hidden by default—enable "show hidden files" in your File Manager).
3. If it exists, try disabling it:
- Rename it to .htaccess-disabled.
- Visit your site—if it works, the .htaccess is corrupted.
4. To fix it:
- In WordPress, go to Settings > Permalinks.
- Click "Save Changes" (without changing anything).
- WordPress will regenerate a correct .htaccess file.

Step 6: Check Server Logs

If the above steps didn't work, your hosting provider's server logs contain detailed error messages.

1. In your control panel, look for "Error Logs" or "Server Logs" (often under "Metrics" or "Tools").
2. Open the most recent log file and look for errors near the time you encountered the white screen.
3. Common errors and solutions:
- "Segmentation fault" or "Core dump": Contact your hosting provider—this is a server-side issue.
- "PHP Parse error": Check for syntax errors in a recently edited file (if you edited functions.php or similar).
- "Connection timeout to database": Your database server may be down (contact your host).

Step 7: Check Disk Space and Resource Limits

If your account runs out of disk space or hits resource limits, WordPress fails.

1. In your control panel, check your disk usage.
2. If you're near your limit, delete old backups, unused files, or large media files.
3. Check for resource limits:
- Look for CPU usage, memory usage, or process limits in your control panel.
- If you're consistently hitting limits, your site may need a bigger hosting plan.

Quick Checklist

If you're in a hurry, try these fixes in order:

1. Disable all plugins (rename /wp-content/plugins to plugins-disabled).
2. Switch to a default theme (Appearance > Themes).
3. Increase PHP memory limit (add define( 'WP_MEMORY_LIMIT', '256M' ); to wp-config.php).
4. Regenerate .htaccess (Settings > Permalinks > Save).
5. Contact your hosting provider if none of the above work.

Most white screens resolve with one of these steps. The debug log (Step 1) is your best friend—it almost always reveals what's actually wrong.