PHP Fatal Error after migration to 2.5.7 - Joomla! Forum - community, help and support

after successful migration 1.6 2.5.7 following error message appear when launching front end of site (after raw format menu):
fatal error: cannot instantiate abstract class jdatabasequery in /storage/content/16/130916/ekeremma.lucere.se/public_html/templates/yougrids/html/mod_menu/yjsg_helperclass.php on line 274
fpa output:

last php error(s) reported :: forum post assistant (v1.2.3) : 31st october 2012 wrote:[31-oct-2012 21:38:11] php fatal error: cannot instantiate abstract class jdatabasequery in /storage/content/16/130916/ekeremma.lucere.se/public_html/templates/yougrids/html/mod_menu/yjsg_helperclass.php on line 274

forum post assistant (v1.2.3) : 31st october 2012 wrote:

basic environment :: wrote:joomla! instance :: joomla! 1.6.1-stable (onward) 07-mar-2011
joomla! platform :: joomla platform 11.4.0-stable (brian kernighan) 03-jan-2012
joomla! configured :: yes | read-only (444) | owner: 130916 (uid: 1/gid: 1) | group: (gid: ) | valid for: 1.6
configuration options :: offline: 1 | sef: 1 | sef suffix: 0 | sef rewrite: 0 | .htaccess/web.config: yes | gzip: 0 | cache: 0 | ftp layer: 0 | ssl: 0 | error reporting: default | site debug: 0 | language debug: 0 | default access: 1 | unicode slugs: 0 | database credentials present: yes

host configuration :: os: linux | os version: 2.6.18-338.19.1.el5.lve0.8.36 | technology: x86_64 | web server: apache | encoding: gzip, deflate | doc root: /storage/content/16/130916/ekeremma.lucere.se/public_html | system tmp writable: yes

php configuration :: version: 5.2.17 | php api: cgi-fcgi | session path writable: unknown | display errors: 1 | error reporting: 6135 | log errors to: /storage/content/16/130916/ekeremma.lucere.se/logs/php-error.log | last known error: 31st october 2012 21:53:00. | register globals: | magic quotes: | safe mode: | open base: | uploads: 1 | max. upload size: 64m | max. post size: 64m | max. input time: 120 | max. execution time: 120 | memory limit: 64m

mysql configuration :: version: 5.1.41-3ubuntu12.10-log (client:5.0.77) | host: --protected-- (--protected--) | collation: utf8_general_ci (character set: utf8) | database size: 1.01 mib | #of tables: 109

detailed environment :: wrote:php extensions :: date (5.2.17) | libxml () | openssl () | pcre () | zlib (1.1) | bcmath () | calendar () | ctype () | curl () | dom (20031129) | hash (1.0) | filter (0.11.0) | ftp () | gd () | gettext () | session () | iconv () | standard (5.2.17) | json (1.2.1) | mbstring () | mcrypt () | mhash () | mysql (1.0) | simplexml (0.1) | spl (0.2) | pdo (1.0.4dev) | pdo_mysql (1.0.2) | pdo_sqlite (1.0.1) | posix () | reflection (0.1) | imap () | shmop () | mysqli (0.1) | soap () | sockets () | exif (1.4 $id: exif.c 293036 2010-01-03 09:23:27z sebastian $) | sysvsem () | sysvshm () | tokenizer (0.1) | xml () | xmlreader (0.1) | xmlwriter (0.1) | xsl (0.1) | zip (1.8.11) | cgi-fcgi () | ioncube loader () | zend optimizer () | zend engine (2.2.0) |
potential missing extensions :: suhosin |

switch user environment (experimental) :: php cgi: yes | server su: yes | php su: yes | custom su (litespeed/cloud/grid): yes
potential ownership issues: no

folder permissions :: wrote:core folders :: images/ (755) | components/ (755) | modules/ (755) | plugins/ (755) | language/ (755) | templates/ (755) | cache/ (755) | logs/ (755) | tmp/ (755) | administrator/components/ (755) | administrator/modules/ (755) | administrator/language/ (755) | administrator/templates/ (755) |

elevated permissions (first 10) ::

extensions discovered :: wrote:components :: site :: com_wrapper (2.5.0) | default (1.0.0) | com_mailto (2.5.0) | wf_emotions_title (2.0.0beta5) | wf_textcase_title (2.0.0beta5) | wf_browser_title (2.0.0beta5) | wf_source_title (2.0.0beta5) | wf_visualchars_title (2.0.0beta5) | wf_print_title (2.0.0beta5) | wf_article_title (2.0.0beta5) | wf_paste_title (2.0.0beta5) | wf_spellchecker_title (2.0.0beta5) | wf_table_title (2.0.0beta5) | wf_style_title (2.0.0beta5) | wf_fullscreen_title (2.0.0beta5) | wf_media_title (2.0.0beta5) | wf_fullpage_title (2.0.0beta5) | wf_imgmanager_title (2.0.0beta5) | wf_directionality_title (2.0.0beta5) | wf_layer_title (2.0.0beta5) | wf_link_title (2.0.0beta5) | wf_cleanup_title (2.0.0beta5) | wf_searchreplace_title (2.0.0beta5) | wf_nonbreaking_title (2.0.0beta5) | wf_inlinepopups_title (2.0.0beta5) | wf_xhtmlxtras_title (2.0.0beta5) | wf_autosave_title (2.0.0beta5) | wf_contextmenu_title (2.0.0beta5) | wf_preview_title (2.0.0beta5) | [youtube] (2.0.0beta5) | wf_aggregator_vimeo_title (2.0.0beta5) | wf_links_joomlalinks_title (2.0.0beta5) | wf_popups_jcemediabox_title (2.0.0beta5) | wf_popups_window_title (2.0.0beta5) | wf_filesystem_joomla_title (2.0.0beta5) | wf_mediaplayer_jceplayer_title (2.0.0beta5) |
components :: admin :: com_installer (2.5.0) | com_media (2.5.0) | com_plugins (2.5.0) | com_newsfeeds (2.5.0) | com_phocagallery (3.2.0) | com_users (2.5.0) | com_banners (2.5.0) | com_content (2.5.0) | com_cpanel (2.5.0) | com_foxcontact (2.0.15) | fox contact joomla 1.5 (-) | com_finder (2.5.0) | com_cache (2.5.0) | com_languages (2.5.0) | com_config (2.5.0) | com_login (2.5.0) | com_messages (2.5.0) | com_modules (2.5.0) | com_weblinks (2.5.0) | com_menus (2.5.0) | com_templates (2.5.0) | com_checkin (2.5.0) | com_joomlaupdate (2.5.0) | com_categories (2.5.0) | com_search (2.5.0) | com_redirect (2.5.0) | unknown (-) | editor - jce (2.0.0beta5) | jce (2.0.0beta5) | com_admin (2.5.0) |

modules :: site :: mod_custom (2.5.0) | mod_whosonline (2.5.0) | mod_articles_latest (2.5.0) | mod_articles_categories (2.5.0) | mod_search (2.5.0) | mod_finder (2.5.0) | mod_weblinks (2.5.0) | mod_articles_archive (2.5.0) | mod_articles_category (2.5.0) | mod_stats (2.5.0) | mod_wrapper (2.5.0) | mod_menu (2.5.0) | mod_languages (2.5.0) | mod_syndicate (2.5.0) | mod_feed (2.5.0) | ari ext menu (1.2.10) | ari ext menu (1.2.10) | mod_articles_news (2.5.0) | fox contact (2.0.15) | easy folder listing (0.3 (j16)) | mod_articles_popular (2.5.0) | mod_users_latest (2.5.0) | mod_footer (2.5.0) | mod_related_items (2.5.0) | mod_breadcrumbs (2.5.0) | mod_banners (2.5.0) | mod_random_image (2.5.0) | mod_login (2.5.0) | mod_weather_gk4 (gk4 1.5) |
modules :: admin :: mod_custom (2.5.0) | mod_submenu (2.5.0) | mod_quickicon (2.5.0) | mod_menu (2.5.0) | mod_feed (2.5.0) | mod_status (2.5.0) | mod_version (2.5.0) | mod_multilangstatus (2.5.0) | mod_unread (1.6.0) | mod_latest (2.5.0) | mod_logged (2.5.0) | mod_toolbar (2.5.0) | mod_popular (2.5.0) | mod_login (2.5.0) | mod_title (2.5.0) | mod_online (1.6.0) |

plugins :: site :: plg_content_loadmodule (2.5.0) | plg_content_example (1.0) | plg_content_pagebreak (2.5.0) | plg_content_geshi (2.5.0) | plg_content_joomla (2.5.0) | plg_content_emailcloak (2.5.0) | plg_content_pagenavigation (2.5.0) | plg_content_finder (2.5.0) | plg_content_vote (2.5.0) | plg_quickicon_extensionupdate (2.5.0) | plg_quickicon_joomlaupdate (2.5.0) | plg_search_content (2.5.0) | plg_search_categories (2.5.0) | plg_search_newsfeeds (2.5.0) | plg_search_weblinks (2.5.0) | plg_search_contacts (2.5.0) | plg_user_example (1.0) | plg_user_joomla (2.5.0) | plg_user_profile (2.5.0) | plg_user_contactcreator (2.5.0) | plg_captcha_recaptcha (2.5.0) | plg_editors_tinymce (3.5.4.1) | plg_editors_codemirror (1.0) | editor - jce (2.0.0beta5) | system - yjmegamenu (1.6) | plg_system_highlight (2.5.0) | plg_system_languagefilter (2.5.0) | plg_system_languagecode (2.5.0) | plg_system_redirect (2.5.0) | plg_system_logout (2.5.0) | plg_system_sef (2.5.0) | plg_system_cache (2.5.0) | plg_system_p3p (2.5.0) | plg_system_log (2.5.0) | plg_system_remember (2.5.0) | google maps (2.18) | plg_system_debug (2.5.0) | plg_extension_example (1.0) | plg_extension_joomla (2.5.0) | plg_editors-xtd_article (2.5.0) | plg_editors-xtd_pagebreak (2.5.0) | plg_editors-xtd_readmore (2.5.0) | plg_editors-xtd_image (2.5.0) | plg_authentification_example (1.6.0) | plg_authentication_joomla (2.5.0) | plg_authentication_gmail (2.5.0) | plg_authentication_ldap (2.5.0) | plg_finder_content (2.5.0) | plg_finder_categories (2.5.0) | plg_finder_newsfeeds (2.5.0) | plg_finder_weblinks (2.5.0) | plg_finder_contacts (2.5.0) |

templates discovered :: wrote:templates :: site :: beez5 (2.5.0) | beez_20 (2.5.0) | yougrids (1.0) | blue tmp (1.6.0) | atomic (2.5.0) | jt001_j16 (1.6.0) | yougrids (1.0) | globalbusiness2-tg (1.6.0) |
templates :: admin :: bluestork (2.5.0) | hathor (2.5.0) |

appreciate , advice solve problem.
rgds/bertil reis

hello again, nobody has advice/ideas on issue? after 2 unsuccessful attempts upgrade 2.5.7 (and 1 successful application) way appears to create new site , load fresh 2.5 joomla , recreate site manually. lot of work , not 1 do. not future numerous new versions of joomla issued frequently. not wish run in these kinds of problems @ every upgrade... :-(