@StefanA SOLVED - (probably this is useful information for many users of TP-Link routers). The problem was on Windows 10 and Google Chrome. I have the latest official version 87.0.4280.141 installed....

@StefanA Update: I can cast to all the Cromecasts and Android units when I connect my laptops to the network via an Ethernet cable. But I can not cast when my laptops are connected via Wifi. So there...

Hi. I have an TP-Link Archer MR600. I can not cast to any of my Chromecast or to my Canal Digital Oneplace (Android). It works perfect when I use my Huawei router so the Chromecasts and the Oneplace...