Views Exposed forms with HS taxonomy placed onto Panel pane causes PHP error with Views (and throws JS error)

is this due to pressflow? I am transferring from a shared to self managed vps server. I am trying to decide if I should use pressflow or ngnix ....I have exposed filters too....

See the updated project page:

Note: the Content Taxonomy module integration is no longer supported. Patches are accepted and committed, but the maintainer does no longer want to fix bugs with this integration. The reason is simple. It's a nightmare. It makes one suicidal. Content Taxonomy is rotten. It needs to die. Thank god it won't be necessary to port this functionality to Drupal 7

LOL.

I was getting this error too.

Both content_taxonomy and hs_content_taxonomy are not installed.

Fatal error: views_exposed_form() [<a href='function.views-exposed-form'>function.views-exposed-form</a>]: The script tried to execute a method or access a property of an incomplete object. Please ensure that the class definition &quot;views_handler_filter_vocabulary_vid&quot; of the object you are trying to operate on was loaded _before_ unserialize() gets called or provide a __autoload() function to load the class definition in /var/www/html/pantheon/dev/sites/all/modules/views/views.module on line 1001

HS worked fine on my form when there was one exposed filter (using HS) but when I added a second filter (without HS) any attempt to select from the HS filter dropdown returned "Received an invalid response from the server." Firebug showed the above error message. This continued even after I removed the second filter.

If I were using the api I would do something like this
$form_state['form_load_files'] = array(drupal_get_path('module', 'taxonomy') . '/views_handler_filter_vocabulary_vid.inc');

But I'm not. The solution I found was to use hook_views_pre_view like so:

function transfair_views_pre_view(&$view, &$display_id, &$args) {
  if ($display_id == "panel_pane_1" && $view->name == "ING_DB") {
    module_load_include('inc','views','handlers/views_handler_filter');
    module_load_include('inc','views','handlers/views_handler_filter_in_operator');
    module_load_include('inc','views','handlers/views_handler_filter_numeric');
    module_load_include('inc','views','modules/taxonomy/views_handler_filter_vocabulary_vid');
    module_load_include('inc','views','handlers/views_handler_filter_many_to_one');
    module_load_include('inc','views','modules/taxonomy/views_handler_filter_term_node_tid');
    module_load_include('inc','hierarchical_select','modules/hs_taxonomy_views_handler_filter_term_node_tid');
    module_load_include('inc','hierarchical_select','modules/hs_taxonomy_views_handler_filter_term_node_tid_depth');
    module_load_include('inc','hierarchical_select','includes/common');
  }
}

Solved it for me...

Apologize for re-opening the issue.. but after experiencing this issue and re-reading the original ticket, I believe eliosh may have miscategorized the issue as Content Taxonomy Views instead of Taxonomy Views. ("I have a view with a taxonomy tid filter exposed")

This also happens for me with a Content pane View display embedded into a Panel.

The exposed HS field works fine in the View Preview, but not on the stand-alone page manager panel page.

The error I am seeing:

"PHP Fatal error:  views_exposed_form(): The script tried to execute a method or access a property of an incomplete object. Please ensure that the class definition "views_handler_filter_boolean_operator" of the object you are trying to operate on was loaded _before_ unserialize() gets called or provide a __autoload() function to load the class definition in views.module on line 1001", request: "POST /hs_taxonomy_views_json/testview/panel_pane_17 HTTP/1.1"

I followed the hook_views_pre_view example but had to watch the error log and manually add the filters applicable to my view until it worked..

Tidying up the issue queue. The 6.x version is no longer supported. Only reopen this if it also applies to the 7.x.