The menu_update_7001() function that was added to the Drupal 7.6 release updates the primary and secondary menu names to their Drupal 7 equivalents but doesn't update existing menu blocks that referenced the old menu names. This causes the following error when upgrading a Drupal 6 site to Drupal 7.6+:
* Notice: Undefined index: primary-links in menu_block_view() (line 462 of /var/www/drupal7/modules/menu/menu.module).
* Notice: Undefined index: secondary-links in menu_block_view() (line 462 of /var/www/drupal7/modules/menu/menu.module).
- Upgrade Drupal 6 site to Drupal 7.6+
- View administration pages
BUG: See error messages above.
- Update the menu block deltas to reference the Drupal 7 equivalent menu name and.
- Add tests for the Drupal 6 to Drupal 7 upgrade path.
Manually update the delta field in the blocks table changing 'primary-links' to 'main-menu' and 'secondary-links' to 'secondary-menu'.
Original report by Alyx Vance
Rename "Primary Links" and "Secondary Links" to their Drupal 7 equivalents.
if menues already exist in the DB, because you have modified manualy in version 7.0 - 7.4 then you get
PDOException: in menu_update_7001() (Zeile 133 von /var/www/web909/html/japan/modules/menu/menu.install).
if you get this exception then do delete in menu_custom table the entries with name main-menu and secondary-menu and be sure thats exist the entries primary-links and secondary-links.
rename in the table menu_links all main-menu and secondary-menu entries to primary-links and secondary-links.
then run update.php again and Drupal should make update correct.
after this you can create new menus in the DB or leave it and change your menue blocks or else
maybe its exist an another way to solve this but i have no idea where