@Kevin_Z Thank you for your replay. But Guest network is working in "Wireless Router Mode"! It is just not available in the administration page once I switch to "Access Point Mode". Therefore the...

I use two WR841N Wifi Routers. One of Hardware Version V13 and one with Hardware Version V14. I can set up a Guest Network with V14 in AP Mode => fine! With hardware version V13 a Guest Network can...