The CW Corner – Is Your PHP Update Breaking Your WordPress Site? Here's the Quick Fix Guide

by Charles Oropallo | Sep 27, 2024 | Do-It-Yourself

You updated PHP on your hosting account and suddenly your WordPress site displays a white screen or error messages. Sound familiar? You're not alone. PHP updates break WordPress sites more often than you'd think, but the good news is that most issues have straightforward fixes.

The problem usually stems from outdated plugins, themes, or even WordPress core files that aren't compatible with newer PHP versions. Think of it like trying to run old software on a brand-new computer – sometimes it just doesn't work without updates.

Don't panic. Here's your step-by-step recovery plan to get your site back online and properly updated.

Step 1: Revert PHP Version Immediately

Your first priority is getting your site back online. Log into your hosting control panel (like cPanel) and find the PHP settings. This might be called "MultiPHP Manager," "PHP Version," or "Select PHP Version."

Switch back to your previous PHP version – usually PHP 7.4 or 8.0. Your site should come back online within minutes. This buys you time to properly diagnose and fix the underlying compatibility issues.

Remember, this is a temporary fix. Running outdated PHP versions leaves your site vulnerable to security threats. PHP 7.4 stopped receiving security updates in November 2022, and even PHP 8.0 support ended in November 2023.

Step 2: Create a Full Site Backup

Before making any changes, backup everything. Use a plugin like UpdraftPlus or your hosting provider's backup tool. You need both your website files and database.

Think of this as insurance. If something goes wrong during the update process, you can restore your site to its current working state. Many hosting providers offer one-click backups through their control panels.

Don't skip this step. I've seen too many sites get worse instead of better because someone tried to fix things without a safety net.

Step 3: Update WordPress Core, Themes, and Plugins

Head to your WordPress dashboard and navigate to Updates. Install all pending updates for WordPress core, your active theme, and plugins. Newer versions often include compatibility patches for recent PHP versions.

Pay special attention to plugins you haven't updated in months or years. Abandoned plugins are the biggest culprits in PHP compatibility issues. If you see plugins that haven't been updated in over two years, consider finding alternatives.

Update your active theme too. Custom themes from developers who no longer provide support can be particularly problematic. If your theme hasn't been updated recently, contact the developer or consider switching to a well-maintained alternative.

Step 4: Run a PHP Compatibility Check

Install the PHP Compatibility Checker plugin by WP Engine. This free tool scans your entire site and generates a report showing which themes and plugins won't work with newer PHP versions.

Run a scan targeting your desired PHP version (usually PHP 8.1 or 8.2). The report will flag specific files and functions that need attention. This gives you a roadmap for what needs fixing before you can safely update PHP.

The scan might take several minutes depending on your site size. Don't close your browser tab while it's running. The detailed report will show you exactly which plugins or themes are causing problems.

Step 5: Test in a Staging Environment

If your hosting provider offers staging sites, use one. Create a copy of your live site where you can safely test the PHP update without affecting visitors.

Apply the PHP update to your staging site first. If everything works correctly there, you can confidently update your live site. If problems occur, you can troubleshoot without any downtime.

Many hosts include staging tools in their control panels. WordPress.com, WP Engine, and SiteGround all offer easy staging environments. Some plugins like WP Staging can create staging sites on any host.

Step 6: Isolate Problematic Components

If your site still breaks after updating everything, you need to identify the specific culprit. Start by deactivating all plugins and switching to a default WordPress theme like Twenty Twenty-Four.

Try the PHP update again. If your site works with all plugins disabled and the default theme active, you know the problem is with a plugin or your theme.

Reactivate plugins one by one, testing your site after each activation. When your site breaks, you've found the problematic plugin. Do the same process with your theme by switching back to it after testing all plugins.

Step 7: Handle Incompatible Extensions

Found the troublemaker? You have several options. First, check if there's a newer version available. Plugin developers often release compatibility updates shortly after new PHP versions.

If no update exists, look for alternative plugins that provide the same functionality. The WordPress plugin directory has thousands of options, and newer plugins typically support current PHP versions.

For premium plugins or themes, contact the developer directly. Many offer compatibility updates for paying customers even if they haven't released public updates.

Sometimes you might need to hire a developer to update custom code or modify a theme. This is especially common with heavily customized sites or older premium themes.

Step 8: Reapply the PHP Update

Once you've resolved all compatibility issues, it's time to update PHP again. Go back to your hosting control panel and select your target PHP version.

Most sites work well with PHP 8.1 or 8.2. These versions offer significant performance improvements over older versions. WordPress officially supports PHP 8.0 and higher, with PHP 8.1 being the recommended version.

Apply the change and test your site thoroughly. Check your homepage, admin area, contact forms, and any special functionality like e-commerce checkout processes.

Step 9: Post-Update Monitoring

After updating PHP, monitor your site closely for the first few days. Clear all caches – server-level caches, plugin caches, and your browser cache.

Check your hosting control panel's error logs for any PHP errors or warnings. Look for the "Error Logs" section in cPanel or similar tools in other hosting panels. WordPress also creates debug logs if you enable debugging in wp-config.php.

Set up website monitoring tools to alert you if your site goes down. Services like UptimeRobot or Pingdom can send email alerts when problems occur.

Prevention Tips for Future Updates

Stay proactive with updates. Install WordPress, theme, and plugin updates regularly instead of letting them accumulate. Regular small updates are much safer than jumping multiple versions at once.

Remove unused plugins and themes. Every piece of code on your site is a potential compatibility problem. If you're not actively using a plugin, delete it completely.

Consider managed WordPress hosting. Companies like WP Engine, Kinsta, and Pressable handle PHP updates more carefully, often testing compatibility before applying updates to your site.

When to Get Professional Help

Some situations require expert assistance. If you're running a mission-critical e-commerce site, have heavily customized code, or feel overwhelmed by the technical steps, consider hiring a WordPress professional.

Custom-built themes and plugins often need developer attention for PHP compatibility. The cost of professional help is usually much less than the revenue lost from extended downtime.

Don't let pride keep your site broken. Sometimes the smartest move is admitting you need help and getting your site fixed quickly and correctly.

Your WordPress site doesn't have to break every time PHP updates. With proper preparation and systematic troubleshooting, you can keep your site running smoothly on current, secure PHP versions. The key is taking it step by step and not rushing the process.