Error on saving 'Answers content type' options when the input format 'full htm' does not exist

I get the error even if I don't make any changes...simply clicking on "Save content type".

Yes, this is a big issue for me because I can't use it the way it is currently...your help is appreciated.

Ok, after some debugging, I found out the problem...

The error is coming from Drupal's includes/form.inc _form_validate function:

         elseif (!isset($options[$elements['#value']])) {
          form_error($elements, $t('An illegal choice has been detected. Please contact the site administrator.'));
          watchdog('form', 'Illegal choice %choice in %name element.', array('%choice' => $elements['#value'], '%name' => empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title']), WATCHDOG_ERROR);
        }

Looks like it has to do with the text format...in my case, $elements['#value'] = full_html, but there is no $options['full_html'].

Why is this module expecting a "full_html" format? It shouldn't assume. Perhaps add something to your documentation about this?

I was user #1.

I believe the issue is that the module assumes there is a text format called "full_html" and in my site, there wasn't. I created one and that solved the problem.

thanks thedut!