Rule to deselect checkbox item? I have a mailchimp subscription content type that add a user to the email list in mailchimp. It works great and adds them to the list.

However, I want deselect that checkbox when they fill out a second content type with a rule. 

So, on creation of content type unsubscribe, check mailchimp list and remove email from list.

I have been search for ideas everywhere and cannot find anything in a tutorial or in Drupal Stack Exchange. Looking for ideas to try and hopefully figure out. Thanks!
if you wont find any other solution without coding to deselect that checkbox you can try to do it via your custom module (if you don't have any you will have to make one - that's different story). 

function YOUR_MODULE_NAME_form_alter(&amp;$form, &amp;$form_state, $form_id){
  $form['field_order_details']['und']['0']['value']['#resizable'] = FALSE;
}


Something similar should work for your checkbox.

See hook_form_alter().