Solved Getting 404 after latest update to 6.9.4 or 7.0.1

Dear members, dear developers,

on my page "Realm667" the forum is broken since Kunena 6.9.4 (and 7.0.1, I tried another update). The backend works just fine, no issues but the frontend forum links all lead to "error 404": 

• www.realm667.com/forum
• www.realm667.com/forum/aktuell
• www.realm667.com/forum/ohneantwort
• ...and so on...

The mainpage can be found here www.realm667.com and I have no idea what's causing this. Hopefully someone has an idea.

Thanks kindly,
best regards,
Dan

I clicked your links as a guest, and everything seems to be working fine.
Maybe try clearing your browser cache.

Works fine for me as well

Okay, this is strange. It doesn't seem to be a problem with the browser cache but with being logged in (or not). Feel free to register and log in and the forum will stop workinh. It works as a guest, it shows 404 if you are logged in.

Yes, if you're registered, that error does appear.
Are you using a security extension?
or have you possibly done something about access rights kunena catoegories ?
And could you post a Kunena configuration report here?

Your menu is wrong. Please check and change.
www.kunena.org/docs/en/troubleshooting/menu-issues
Furthermore you seem to have an English site and your Kunena menu is in German???