I just finished upgrading to 4.2.19. Initially, I received the same error others had received: as noted in this thread http://www.amember.com/forum/threads/trouble-with-last-amember-upgrade-4-2-19.17065/ So I did what another user recommended and upgraded the db separately at admin-upgrade-db and got to the upgrade successful page and upon logging back into the amem control panel the version info confirms the upgrade is complete. However, I have noticed a lot of strange errors, and aMember is closed for the weekend. I submitted a ticket in helpdesk - but if anyone has any advice it is much appreciated. It is not auto-logging into wordpress anymore when user logs into amember, so no members can reach protected wp content. HUGE issue. When I go to /login page and click the login button nothing happens, but if I click a navigational link I am actually logged in, it just doesn't redirect to /member page. UGLY issue. When I tried to edit admin user accounts, it says 'loading' when I click the edit button, but nothing happens. When I try to add a new admin user - it gives me a database error. ODD issue. When I try to rebuild the WP or Core DB - the buttons become grayed out and the box appears, but nothing happens. CONCERNING issue.