Notice: Constant DATE_RFC7231 already defined in includes/ on line 258

Drupal 7:

  • Open /includes/
  • Go to line number 258
  • Comment out the following line
    //define(‘DATE_RFC7231’, ‘D, d M Y H:i:s \G\M\T’);
  • Then add following line
    if (!defined(‘DATE_RFC7231’)) {
    define(‘DATE_RFC7231’, ‘D, d M Y H:i:s \G\M\T’);
  • Save and you are good to go 🙂
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