I am trying to create a rule based on the blog post here: https://civicrm.org/blog/petednz/creating-drupal-users-made-easy-for-single-or-multiple-contacts-via-civi-imports-and
I'm recreating the rule manually but when I try to create the action 'Create linked drupal user account' I get this error, does anyone know why?
2016/11/07 15:09:43 [error] 28899#28899: *113846 FastCGI sent in stderr: "PHP message: PHP Fatal error: Unsupported operand types in /var/www/xxxxxx/includes/form.inc on line 2760" while reading response header from upstream, client: x.x.x.x, server: example.com, request: "POST /system/ajax HTTP/1.1", upstream: "fastcgi://unix:/var/run/php5-fpm.sock:", host: "example.com", referrer: "https://example.com/admin/config/workflow/rules/reaction/manage/rules_entity_tag_create_drupal_user/add/1/action"
2016/11/07 15:09:43 [error] 28899#28899: *113846 FastCGI sent in stderr: "PHP message: PHP Fatal error: Unsupported operand types in /var/www/xxxxxx/includes/form.inc on line 2760" while reading response header from upstream, client: x.x.x.x, server: example.com, request: "POST /system/ajax HTTP/1.1", upstream: "fastcgi://unix:/var/run/php5-fpm.sock:", host: "example.com", referrer: "https://example.com/admin/config/workflow/rules/reaction/manage/rules_entity_tag_create_drupal_user/add/1/action"