Can't Add Sub Menu

Can't Add Sub Menu... getting errors

Fatal error: Cannot create references to/from string offsets nor overloaded objects in /home/newm0de/public_html/includes/common.inc on line 6660

function drupal_array_set_nested_value(array &$array, array $parents, $value, $force = FALSE) {
$ref = &$array;
foreach ($parents as $parent) {
// PHP auto-creates container arrays and NULL entries without error if $ref
// is NULL, but throws an error if $ref is set, but not an array.
if ($force && isset($ref) && !is_array($ref)) {
$ref = array();
}
$ref = &$ref[$parent];
}
$ref = $value;
}