The bulk of the code in WordPress websites is written in a language called PHP. The code interacts with a database to produce web pages that are displayed within your browser window.

PHP is installed on a webserver and is available in multiple versions, currently up to version 8. There was no PHP version 6. Typically you may see version 5.4, 5.5, 5.6, 7.0, 7.1, 7.2, 7.3, 7.4 & 8.0.

PHP versions 5.x are no longer supported by WordPress and WordPress plugins are usually written for version 7 and upwards. Similarly legacy plugins written for PHP 5.x may not work with systems designed for version. If you server is running PHP version 5.6 or below you may have issues with newer versions of WordPress. Similarly if you server is running PHP 7.x or above, you may find that old legacy plugins or themes break your website.

In an ideal world you should keep PHP, WordPress, your theme and all plugins updated to the latest versions.

In some instances, an incompatibility may cause a component to break. In the example above we have deliberately broken a plugin and are receiving an error message. This error message may also come by email.

In this case, we can see that the error is within the plugin "visit-notifications", specifically in the file located at /home/wpsandbo/public_html/wp-content/plugins/visit-notifications/visit-notification.php

We will need to disable this plugin manually.

You will need to access your file manager to do this. How you do this will depend on your webhost. In this examples we use cPanel, but the concept is the same across all platforms.

Navigate to the WordPress Plugins folder. This is usually at {website root}/wp-content/plugins. The {website root} will depend on your webhost but is often /public_html or /httpd

Rename the plugin folder, in this case visit-notification to visit-notifications.bak

This will disable the plugin. You will now be able to access and log into your website.