after upgrading from 6.13 to 6.14, error message when enabling back modules

I just performed a drupal upgrade from 6.13 to 6.14. Everything went alright until I tried to enable back the modules, and then I get the error message below. My site www.testsite.aspk.com.tw

user warning: Duplicate entry 'field_image_cache' for key 1 query: INSERT INTO drup_content_node_field (field_name, type, global_settings, required, multiple, db_storage, module, db_columns, active, locked) VALUES ('field_image_cache', 'filefield', 'a:3:{s:10:\"list_field\";s:1:\"0\";s:12:\"list_default\";i:1;s:17:\"description_field\";s:1:\"0\";}', 0, 1, 0, 'filefield', 'a:3:{s:3:\"fid\";a:3:{s:4:\"type\";s:3:\"int\";s:8:\"not null\";b:0;s:5:\"views\";b:1;}s:4:\"list\";a:4:{s:4:\"type\";s:3:\"int\";s:4:\"size\";s:4:\"tiny\";s:8:\"not null\";b:0;s:5:\"views\";b:1;}s:4:\"data\";a:3:{s:4:\"type\";s:4:\"text\";s:9:\"serialize\";b:1;s:5:\"views\";b:1;}}', 1, 0) in /home2/aspkcomt/public_html/testsite/includes/common.inc on line 3468.
user warning: Duplicate entry 'field_image_cache-product' for key 1 query: INSERT INTO drup_content_node_field_instance (field_name, type_name, weight, label, widget_type, widget_settings, display_settings, description, widget_module, widget_active) VALUES ('field_image_cache', 'product', -2, 'Image', 'imagefield_widget', 'a:0:{}', 'a:4:{s:5:\"label\";a:1:{s:6:\"format\";s:6:\"hidden\";}s:6:\"teaser\";a:1:{s:6:\"format\";s:6:\"hidden\";}s:4:\"full\";a:1:{s:6:\"format\";s:6:\"hidden\";}i:4;a:1:{s:6:\"format\";s:6:\"hidden\";}}', '', 'imagefield', 0) in /home2/aspkcomt/public_html/testsite/includes/common.inc on line 3468.