Folks,
We have a really strange problem with a medium size site that has been upgraded from a D6 to a D7 (7.10).
The upgrade was fairly easy (as easy as such processes can be), and the site is running as expected except for one pretty major thing:
No new menu items can be added.
And with adding menu items I don't mean creating menu items in user menus manually (that works), but having D7 itself add menu paths as a response to installing modules, creating content types and much more.
It simply doesn't happen!
If we add a new content type called test_type, we should get a new menu item under node/add, but we don't. The path node/add/test_type leads nowhere and checking the menu_links and menu_router table tells us that they don't exist.
Same thing if we activate a module, say Dashboard. Normally we'd get a new link to click in the admin menu and the path admin/dashboard should lead to the Dashboard, but neither works.
If we add a menu item to hook_menu in one of our own modules, say /testing_menus as a callback, which returns some sort of banal page content, I get a page not found when trying to reach /testing_menus.
We have tried many things: Flushing caches, running update, uninstalling and reinstalling modules, fiddling permissions. Nothing changes this behavior.