The site health check could not be performed

WordPress runs a Site Health routine that gathers server and configuration data. When the routine hits a fatal PHP error, it stops and the dashboard shows a red banner that says the check could not be performed. The error usually stems from a mismatched core file, a broken cron event, or a PHP version that does not support the arithmetic used in the health‑check code. The failure prevents WordPress from reporting status and info, leaving the Site Health page empty.