id summary reporter owner description type status component version severity resolution keywords cc stage has_patch needs_docs needs_tests needs_better_patch easy ui_ux 22426 Django >= 1.6.0 can't handle old style messages cookie iivvoo ofirov "The message cookie format has changed in Django 1.5.x, Django 1.6.x no longer supports the old format. If you upgrade your project from Django 1.4.x directly to 1.6.x (skipping the 1.5 release), your application will fail quickly on old-style message cookies: {{{ Exception Type: IndexError Exception Value: list index out of range Exception Location: (...) django/contrib/messages/storage/cookie.py in process_messages, line 37 }}} Django 1.5 contained some backward compatibility to handle both styles: https://github.com/django/django/commit/9e7183073f64e541587e8dcfd8bb3ddeb47f8162 but this code is no longer present in Django 1.6.2 Since you can't ask all your users to delete their cookies if they run into this error, there's no easy/quick workaround. It's not uncommon for projects to skip a version. Also, Django 1.4.x is LTS and people may jump from LTS release to LTS release, which means they will also run into this issue. " Bug closed contrib.messages 1.6 Release blocker fixed messages, cookie, 1.4 Accepted 1 0 0 0 0 0