Why this happens

The plugin's code requires a PHP version, WordPress version, or another plugin that your site doesn't currently have. Rather than silently failing, WordPress catches the fatal error during activation and rolls the plugin back to prevent it from breaking your entire site.

Step-by-step fix

  1. Check the plugin's requirements on its WordPress.org page - confirm your PHP/WordPress version matches.
  2. If your PHP version is outdated, update it from cPanel's 'Select PHP Version' option.
  3. Disable other plugins one by one to check for a conflict.
  4. If it still doesn't work, post the error on the plugin developer's support forum.

How to prevent it happening again