'Missing handler: history_user timestamp field'

Can you try the latest -dev version, see if it works there?
I think a fix was committed.

I installed the latest dev version and I'm getting the same error.

Okay then.

Just to clarify, I didn't download from CVS, I'm unable to. Perhaps the fix was in CVS and not in dev.

You can use the dev version on the project page.

Alternative can you export the the view so that someone is possible to reproduce the problem on his local machine?

I'm having the same result... with fresh install of the -dev version doesn't seem to be any point in exporting the view, since it's the default view that is installed by VBO.

D7, Views 7.x-3.0-alpha1, VBO 7.x-3.x-dev, PHP 5.3

messages are:

Debug: 'Missing handler: history_user timestamp field' in views_get_handler() (line 841 of .../drupal/7/sites/all/modules/views/views.module).
Notice: Undefined property: stdClass::$unknown in views_handler_field->render() (line 713 of .../drupal/7/sites/all/modules/views/handlers/views_handler_field.inc). (repeated once for each content item in the site).
Notice: Undefined index: row_class in views_plugin_style->get_row_class() (line 104 of /etc/drupal/7/sites/all/modules/views/plugins/views_plugin_style.inc). (repeated once for each content item in the site).

Any other info I can add?

Quote myself

Alternative can you export the the view so that someone is possible to reproduce the problem on his local machine?

$view = new view;
$view->name = 'admin_content';
$view->description = 'Emulates the Drupal content administration page.';
$view->tag = '';
$view->base_table = 'node';
$view->human_name = '';
$view->core = 0;
$view->api_version = '3.0-alpha1';
$view->disabled = FALSE; /* Edit this to true to make a default view disabled initially */

/* Display: Defaults */
$handler = $view->new_display('default', 'Defaults', 'default');
$handler->display->display_options['title'] = 'Content';
$handler->display->display_options['access']['type'] = 'perm';
$handler->display->display_options['access']['perm'] = 'administer nodes';
$handler->display->display_options['cache']['type'] = 'none';
$handler->display->display_options['query']['type'] = 'views_query';
$handler->display->display_options['exposed_form']['type'] = 'basic';
$handler->display->display_options['pager']['type'] = 'full';
$handler->display->display_options['pager']['options']['items_per_page'] = 20;
$handler->display->display_options['style_plugin'] = 'bulk';
$handler->display->display_options['style_options']['columns'] = array(
'title' => 'title',
'timestamp' => 'title',
'type' => 'type',
'name' => 'name',
'status' => 'status',
'edit_node' => 'edit_node',
);
$handler->display->display_options['style_options']['default'] = '-1';
$handler->display->display_options['style_options']['info'] = array(
'title' => array(
'sortable' => 1,
'align' => '',
'separator' => ' ',
),
'timestamp' => array(
'align' => '',
'separator' => '',
),
'type' => array(
'sortable' => 1,
'align' => '',
'separator' => '',
),
'name' => array(
'sortable' => 1,
'align' => '',
'separator' => '',
),
'status' => array(
'sortable' => 0,
'align' => '',
'separator' => '',
),
'edit_node' => array(
'align' => '',
'separator' => '',
),
);
$handler->display->display_options['style_options']['override'] = 1;
$handler->display->display_options['style_options']['sticky'] = 0;
$handler->display->display_options['style_options']['selected_operations'] = array(
'node_assign_owner_action' => 'node_assign_owner_action',
'views_bulk_operations_delete_node_action' => 'views_bulk_operations_delete_node_action',
'views_bulk_operations_script_action' => 'views_bulk_operations_script_action',
'node_make_sticky_action' => 'node_make_sticky_action',
'node_make_unsticky_action' => 'node_make_unsticky_action',
'views_bulk_operations_fields_action' => 'views_bulk_operations_fields_action',
'views_bulk_operations_taxonomy_action' => 'views_bulk_operations_taxonomy_action',
'node_promote_action' => 'node_promote_action',
'node_publish_action' => 'node_publish_action',
'node_unpromote_action' => 'node_unpromote_action',
'node_unpublish_action' => 'node_unpublish_action',
'node_unpublish_by_keyword_action' => 'node_unpublish_by_keyword_action',
);
$handler->display->display_options['style_options']['execution_type'] = '1';
$handler->display->display_options['style_options']['display_type'] = '0';
$handler->display->display_options['style_options']['skip_confirmation'] = 0;
$handler->display->display_options['style_options']['display_result'] = 1;
$handler->display->display_options['style_options']['merge_single_action'] = 1;
$handler->display->display_options['style_options']['hide_select_all'] = 0;
/* Empty text: Global: Text area */
$handler->display->display_options['empty']['text']['id'] = 'area';
$handler->display->display_options['empty']['text']['table'] = 'views';
$handler->display->display_options['empty']['text']['field'] = 'area';
$handler->display->display_options['empty']['text']['empty'] = FALSE;
$handler->display->display_options['empty']['text']['content'] = 'There are no objects satisfying the filter settings. Try changing them to get some results.';
$handler->display->display_options['empty']['text']['format'] = '1';
/* Field: Node: Title */
$handler->display->display_options['fields']['title']['id'] = 'title';
$handler->display->display_options['fields']['title']['table'] = 'node';
$handler->display->display_options['fields']['title']['field'] = 'title';
$handler->display->display_options['fields']['title']['link_to_node'] = 1;
/* Field: Broken/missing handler */
$handler->display->display_options['fields']['timestamp']['id'] = 'timestamp';
$handler->display->display_options['fields']['timestamp']['table'] = 'history_user';
$handler->display->display_options['fields']['timestamp']['field'] = 'timestamp';
$handler->display->display_options['fields']['timestamp']['label'] = 'New?';
/* Field: Node: Type */
$handler->display->display_options['fields']['type']['id'] = 'type';
$handler->display->display_options['fields']['type']['table'] = 'node';
$handler->display->display_options['fields']['type']['field'] = 'type';
$handler->display->display_options['fields']['type']['link_to_node'] = 0;
/* Field: User: Name */
$handler->display->display_options['fields']['name']['id'] = 'name';
$handler->display->display_options['fields']['name']['table'] = 'users';
$handler->display->display_options['fields']['name']['field'] = 'name';
$handler->display->display_options['fields']['name']['label'] = 'Author';
$handler->display->display_options['fields']['name']['link_to_user'] = 1;
/* Field: Node: Published */
$handler->display->display_options['fields']['status']['id'] = 'status';
$handler->display->display_options['fields']['status']['table'] = 'node';
$handler->display->display_options['fields']['status']['field'] = 'status';
$handler->display->display_options['fields']['status']['not'] = 0;
/* Field: Node: Edit link */
$handler->display->display_options['fields']['edit_node']['id'] = 'edit_node';
$handler->display->display_options['fields']['edit_node']['table'] = 'node';
$handler->display->display_options['fields']['edit_node']['field'] = 'edit_node';
$handler->display->display_options['fields']['edit_node']['label'] = 'Edit';
/* Sort criterion: Node: Updated date */
$handler->display->display_options['sorts']['changed']['id'] = 'changed';
$handler->display->display_options['sorts']['changed']['table'] = 'node';
$handler->display->display_options['sorts']['changed']['field'] = 'changed';
$handler->display->display_options['sorts']['changed']['order'] = 'DESC';
/* Filter: Node: Title */
$handler->display->display_options['filters']['title']['id'] = 'title';
$handler->display->display_options['filters']['title']['table'] = 'node';
$handler->display->display_options['filters']['title']['field'] = 'title';
$handler->display->display_options['filters']['title']['operator'] = 'contains';
$handler->display->display_options['filters']['title']['exposed'] = TRUE;
$handler->display->display_options['filters']['title']['expose']['operator'] = 'title_op';
$handler->display->display_options['filters']['title']['expose']['label'] = 'Title contains';
$handler->display->display_options['filters']['title']['expose']['identifier'] = 'title';
/* Filter: Node: Type */
$handler->display->display_options['filters']['type']['id'] = 'type';
$handler->display->display_options['filters']['type']['table'] = 'node';
$handler->display->display_options['filters']['type']['field'] = 'type';
$handler->display->display_options['filters']['type']['exposed'] = TRUE;
$handler->display->display_options['filters']['type']['expose']['operator'] = 'type_op';
$handler->display->display_options['filters']['type']['expose']['label'] = 'Node: Type';
$handler->display->display_options['filters']['type']['expose']['identifier'] = 'type';
/* Filter: Node: Promoted to front page */
$handler->display->display_options['filters']['promote']['id'] = 'promote';
$handler->display->display_options['filters']['promote']['table'] = 'node';
$handler->display->display_options['filters']['promote']['field'] = 'promote';
$handler->display->display_options['filters']['promote']['value'] = 'All';
$handler->display->display_options['filters']['promote']['exposed'] = TRUE;
$handler->display->display_options['filters']['promote']['expose']['label'] = 'Promoted';
$handler->display->display_options['filters']['promote']['expose']['identifier'] = 'promote';
/* Filter: Node: Published */
$handler->display->display_options['filters']['status']['id'] = 'status';
$handler->display->display_options['filters']['status']['table'] = 'node';
$handler->display->display_options['filters']['status']['field'] = 'status';
$handler->display->display_options['filters']['status']['value'] = 'All';
$handler->display->display_options['filters']['status']['exposed'] = TRUE;
$handler->display->display_options['filters']['status']['expose']['label'] = 'Published';
$handler->display->display_options['filters']['status']['expose']['identifier'] = 'status';
/* Filter: Node: Sticky */
$handler->display->display_options['filters']['sticky']['id'] = 'sticky';
$handler->display->display_options['filters']['sticky']['table'] = 'node';
$handler->display->display_options['filters']['sticky']['field'] = 'sticky';
$handler->display->display_options['filters']['sticky']['value'] = 'All';
$handler->display->display_options['filters']['sticky']['exposed'] = TRUE;
$handler->display->display_options['filters']['sticky']['expose']['label'] = 'Sticky';
$handler->display->display_options['filters']['sticky']['expose']['identifier'] = 'sticky';

/* Display: Page */
$handler = $view->new_display('page', 'Page', 'page');
$handler->display->display_options['path'] = 'admin/content/node2';
$translatables['admin_content'] = array(
t('Defaults'),
t('Content'),
t('more'),
t('Apply'),
t('Reset'),
t('Sort By'),
t('Asc'),
t('Desc'),
t('Items per page'),
t('- All -'),
t('Offset'),
t('There are no objects satisfying the filter settings. Try changing them to get some results.'),
t('Title'),
t('New?'),
t('Type'),
t('Author'),
t('Published'),
t('Edit'),
t('Title contains'),
t('Node: Type'),
t('Promoted'),
t('Sticky'),
t('Page'),
);

Can you remove and re-add the history field?
This should solve all problems you have.

@dereine, yes, that worked, thanks! Not sure what happened, but I missed an "obvious" bad reference in the views settings.

Cheers :)