Ошибка на сайте

Recoverable fatal error: Argument 1 passed to xmlsitemap_node_create_link() must be an instance of stdClass, boolean given, called in /xmlsitemap/xmlsitemap_node/xmlsitemap_node.module on line 28 and defined в функции xmlsitemap_node_create_link() (строка 194 в файле /xmlsitemap_node/xmlsitemap_node.module).

) Warning: Cannot modify header information - headers already sent by (output started at /includes/common.inc:2777) in /includes/bootstrap.inc on line 1486
Call Stack
# Time Memory Function Location
1 0.0001 236560 {main}( ) ../index.php:0
2 0.2789 29037024 menu_execute_active_handler( ) ../index.php:21
3 0.4061 33184400 drupal_deliver_page( ) ../menu.inc:542
4 0.4074 33255904 boost_deliver_html_page( ) ../common.inc:2625
5 0.4074 33256392 drupal_deliver_html_page( ) ../boost.module:1490
6 0.9884 48311608 drupal_page_footer( ) ../common.inc:2756
7 0.9930 48366496 system_run_automated_cron( ) ../common.inc:2784
8 0.9930 48366856 drupal_cron_run( ) ../system.module:3560
9 1.4618 49230512 module_invoke( ) ../common.inc:5420
10 1.4618 49230864 call_user_func_array:{/module.inc:926} ( ) ../module.inc:926
11 1.4618 49231168 xmlsitemap_node_cron( ) ../module.inc:926
12 1.4635 49238080 xmlsitemap_node_create_link( ) ../xmlsitemap_node.module:28
13 1.4635 49238984 _drupal_error_handler( ) ../xmlsitemap_node.module:194
14 1.4636 49239064 _drupal_error_handler_real( ) ../bootstrap.inc:2591
15 1.4638 49253624 _drupal_log_error( ) ../errors.inc:75
16 1.4644 49254192 drupal_add_http_header( ) ../errors.inc:214
17 1.4644 49254880 drupal_send_headers( ) ../bootstrap.inc:1416
18 1.4644 49256360 header ( ) ../bootstrap.inc:1486