I am having same issue with connecting SYSTXCCITC01-A to my RBE772

Was this ever resolved?  I am having same issue with connecting SYSTXCCITC01-A to my RBE772 and I have tried all options mentioned...except setting CTS/RTS threshold to 2347 as this option to update does not appear in the settings interface.

So with IoT network enabled and set for 2.4Ghz and WPA2, the device won't connect at all?

Try a 2ndary wireless router or AP with same SSID name and PW as the Orbi system to connect the device too long enough to get the device connected to a signal, then turn OFF the 2ndary router/AP and see if the device will migrate to the Orbi signal?

Could try a external wifi extender to see if the device would connect to an extender that can connect to the Orbi system.

What FW version is on the 770 series? 

DEJohnson wrote:

I am having same issue with connecting SYSTXCCITC01-A to my RBE772

Googling says that it doesn't support WPA3, so make sure you have WPA2 enabled in the settings.  Best to put this on the IoT network, as it is WiFi 4.