Bad redirection after update

hy,
i just made the update to 4.1 version and have an error now. the domain is http://www.neubruck.at, the slug defined in the settings is “kalender”. if i visit http://www.neubruck.at/kalender, it redirects me to “http://kalender//?tribe_event_display=past”…

note that you can not visit neubruck.at, you have to visit neubruck.at/preview if you wish to see the rest of the site…

i tried to save permalink structure again, save settings form plugin again, change slug, …

the single events can be displayed as usual.

thanks for your hints 😉
matt

https://ww.wp.xz.cn/plugins/the-events-calendar/