I'm getting this unrecoverable error when upgrading from 6.20 to 7.0:
An AJAX HTTP error occurred. HTTP Result Code: 500 Debugging information follows. Path: http://[site]/update.php?id=533&op=do StatusText: Service unavailable (with message) ResponseText: PDOException: SQLSTATE[42S02]: Base table or view not found: 1146 Table '[db].block_node_type' doesn't exist: SELECT module, delta, type FROM {block_node_type}; Array ( ) in node_block_list_alter() (line 2374 of /home/rokur/[site]/modules/node/node.module).
My site is quite standard Drupal 6.20, except for these modules: AddToAny 6.x-3.3, BUEditor 6.x-2.2, Facebook Like Button, Mollom 6.x-1.15, Pathauto 6.x-1.5, Token 6.x-1.15, Archive 6.x-1.4, Google Analytics 6.x-3.2, and an additional theme Pixture Reloaded 6.x-3.2.
I also try to keep optional core modules to a minimum: Color, Comment, Contact, Database Logging, Forum, Help, Locale, Menu, OpenID, Path, PHP Filter, Ping, Profile, Search, Statistics, Syslog, Taxonomy, Throttle, Tracker, Trigger, Update Status and Upload.
The site status report says that everything is OK.
I disabled the additional modules and the additional theme, before upgrading. I also changed the default language from additional Faroese to English, just to be as close to standard as possible.