WordPress 5.1

WordPress 5.1 added early Site Health functionality, including notices that identify installations running an outdated PHP version and guidance for improving the server environment. It raised the PHP requirement for new WordPress installations to PHP 5.6, while existing installations on older PHP could continue operating with warnings. The release also included block-editor refinements and developer-facing changes, notably multisite metadata support and updates to scheduled-task handling. Compared with the preceding WordPress line, it placed more emphasis on detecting unsupported server configurations before they caused operational or security problems.

WordPress 5.1 has reached end of life, so remaining on it leaves the site without fixes delivered for later WordPress core vulnerabilities, defects, compatibility issues, and accessibility improvements. Its original PHP baseline is itself obsolete, and servers kept on similarly old PHP versions compound the risk through unpatched runtime vulnerabilities and limited compatibility with current plugins, themes, and hosting tooling. A site may appear to work until a plugin, theme, integration, browser behavior, or hosting change exposes the gap; recovery then becomes an urgent migration rather than a controlled one. WooCommerce is a plugin that runs on WordPress, so a WooCommerce store is a WordPress site, and its WordPress version matters to it just as much as its WooCommerce version does.

Inventory the site’s WordPress core version, active and inactive plugins, theme, custom code, PHP version, database version, integrations, and scheduled jobs. Take tested backups of both files and database, then clone the site into a staging environment that matches production closely. Move the staging environment to a currently supported PHP version and update WordPress through appropriate intermediate compatibility checks, updating or replacing plugins and themes that are no longer maintained or compatible. Test critical paths rather than only the homepage: authentication, editorial workflows, forms, search, email delivery, caching, media uploads, API integrations, scheduled tasks, and any custom functionality. For WooCommerce, additionally test product browsing, cart and checkout flows, payment and tax services, order emails, stock updates, subscriptions or bookings if used, and webhook integrations. Resolve warnings and errors in staging, plan a rollback and maintenance window, deploy the validated upgrade, and monitor logs, transactions, scheduled tasks, and user reports after deployment.