Improvvisamente Drupal non funziona più

Salve a tutti improvvisamente oggi il drupal montato sul mio sito ha smesso di funzionare dopo mesi di normale funzionamento. Quando accedo a qualsiasi pagina ottengo questi errori:

Warning: Table 'Sql12761_4.drupal_access' doesn't exist query: SELECT CASE WHEN status=1 THEN 0 ELSE 1 END FROM drupal_access WHERE type = 'host' AND LOWER('87.5.80.3') LIKE LOWER(mask) ORDER BY status DESC LIMIT 0, 1 in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_users' doesn't exist query: SELECT u.*, s.* FROM drupal_users u INNER JOIN drupal_sessions s ON u.uid = s.uid WHERE s.sid = 'ed15160c2e41e8c8181b9239f443da08' in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc:172) in /web/htdocs/www.vecio.it/home/cms/includes/bootstrap.inc on line 862

Warning: Table 'Sql12761_4.drupal_cache' doesn't exist query: SELECT data, created, headers, expire FROM drupal_cache WHERE cid = 'variables' in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_variable' doesn't exist query: SELECT * FROM drupal_variable in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_cache' doesn't exist query: LOCK TABLES drupal_cache WRITE in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_cache' doesn't exist query: UPDATE drupal_cache SET data = 'N;', created = 1200146059, expire = 0, headers = '' WHERE cid = 'variables' in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_cache_page' doesn't exist query: SELECT data, created, headers, expire FROM drupal_cache_page WHERE cid = 'http://www.vecio.it/cms/admin' in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Cannot modify header information - headers already sent by (output started at /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc:172) in /web/htdocs/www.vecio.it/home/cms/includes/bootstrap.inc on line 531

Warning: Cannot modify header information - headers already sent by (output started at /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc:172) in /web/htdocs/www.vecio.it/home/cms/includes/bootstrap.inc on line 532

Warning: Cannot modify header information - headers already sent by (output started at /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc:172) in /web/htdocs/www.vecio.it/home/cms/includes/bootstrap.inc on line 533

Warning: Cannot modify header information - headers already sent by (output started at /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc:172) in /web/htdocs/www.vecio.it/home/cms/includes/bootstrap.inc on line 534

Warning: Table 'Sql12761_4.drupal_url_alias' doesn't exist query: SELECT COUNT(pid) FROM drupal_url_alias in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_system' doesn't exist query: SELECT * FROM drupal_system WHERE type = 'theme' in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_watchdog' doesn't exist query: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Cannot modify header information - headers already sent by (output started at /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc:172) in /web/htdocs/www.vecio.it/home/cms/includes/common.inc on line 141.', 2, '', 'http://www.vecio.it/cms/admin', '', '87.5.80.3', 1200146059) in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_watchdog' doesn't exist query: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Table 'Sql12761_4.drupal_system' doesn't exist\nquery: SELECT name, filename, throttle FROM drupal_system WHERE type = 'module' AND status = 1 ORDER BY weight ASC, filename ASC in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172.', 2, '', 'http://www.vecio.it/cms/admin', '', '87.5.80.3', 1200146059) in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_watchdog' doesn't exist query: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Table 'Sql12761_4.drupal_cache_menu' doesn't exist\nquery: SELECT data, created, headers, expire FROM drupal_cache_menu WHERE cid = '0:en' in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172.', 2, '', 'http://www.vecio.it/cms/admin', '', '87.5.80.3', 1200146059) in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_watchdog' doesn't exist query: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Table 'Sql12761_4.drupal_cache_menu' doesn't exist\nquery: LOCK TABLES drupal_cache_menu WRITE in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172.', 2, '', 'http://www.vecio.it/cms/admin', '', '87.5.80.3', 1200146059) in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_watchdog' doesn't exist query: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Table 'Sql12761_4.drupal_cache_menu' doesn't exist\nquery: UPDATE drupal_cache_menu SET data = 'a:4:{s:10:\\"path index\\";a:0:{}s:5:\\"items\\";a:2:{i:0;a:5:{s:4:\\"path\\";s:0:\\"\\";s:5:\\"title\\";s:0:\\"\\";s:4:\\"type\\";i:1;s:3:\\"pid\\";i:1;s:8:\\"children\\";a:1:{i:0;i:1;}}i:1;a:6:{s:3:\\"pid\\";i:0;s:4:\\"path\\";s:0:\\"\\";s:5:\\"title\\";s:10:\\"Navigation\\";s:6:\\&amp in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_watchdog' doesn't exist query: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Cannot modify header information - headers already sent by (output started at /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc:172) in /web/htdocs/www.vecio.it/home/cms/includes/common.inc on line 141.', 2, '', 'http://www.vecio.it/cms/admin', '', '87.5.80.3', 1200146059) in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_watchdog' doesn't exist query: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Table 'Sql12761_4.drupal_watchdog' doesn't exist\nquery: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'page not found', 'admin', 1, '', 'http://www.vecio.it/cms/admin', '', '87.5.80.3', 1200146059) in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172.', 2, '', 'http://www.vecio.it/cms/admin', '', '87.5.80.3', 1200146059) in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Fatal error: Call to undefined function: block_list() in /web/htdocs/www.vecio.it/home/cms/includes/theme.inc on line 1018

Warning: Table 'Sql12761_4.drupal_watchdog' doesn't exist query: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Table 'Sql12761_4.drupal_sessions' doesn't exist\nquery: SELECT sid FROM drupal_sessions WHERE sid = 'ed15160c2e41e8c8181b9239f443da08' in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172.', 2, '', 'http://www.vecio.it/cms/admin', '', '87.5.80.3', 1200146059) in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

Warning: Table 'Sql12761_4.drupal_watchdog' doesn't exist query: INSERT INTO drupal_watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Table 'Sql12761_4.drupal_sessions' doesn't exist\nquery: INSERT INTO drupal_sessions (sid, uid, cache, hostname, session, timestamp) VALUES ('ed15160c2e41e8c8181b9239f443da08', 0, 0, '87.5.80.3', 'messages|a:1:{s:5:\\"error\\";a:7:{i:0;s:223:\\"warning: Cannot modify header information - headers already sent by (output started at /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc:172) in /web/htdocs/www.vecio.it/home/cms/includes/common.inc on line 141.\\";i:1;s:292:\\"user warning: Table 'Sql12761_4.drupal_system' doesn't exist\\nquery: SELECT name, filename, thrott in /web/htdocs/www.vecio.it/home/cms/includes/database.mysql.inc on line 172

il Mysql che utilizzo funziona bene, perchè ho un phpbb installato sullo stesso sito che usa lo stesso Db e non sta avendo problemi. Qualcuno mi da una mano a capire cosa è successo? non so proprio dove iniziare...Grazie