@Kai_F Hi, Currently OneMesh doesn't work between two routers. https://www.tp-link.com/en/onemesh/

@Benjami Hi, Is the ISP that is providing the IPTV service to you the same ISP that gave you the Archer C5 V4 router? If yes, then it would probably be best to ask your ISP how to make their IPTV...

@Evvivame1 Hi, Check if this configuration guide is of any help to you https://www.tp-link.com/en/support/faq/1758/ .

@Ilan316 Hi, It may depend on the hardware version of the Archer C7. Which version is your Archer C7? (the version number "Ver:x.x" should be printed on the label on the underside of the router)...

@Ondulado Hi, Since all three routers are of the same model TL-WR841N you should be able to single out where the problem lies by interchanging the routers with each other. So, Router 2 and Router 3...

@Ryarbrough I don't want to call it a "suggested" workaround, but if you open that world-famous video platform we all know and search for "add external antenna to router", then you will find plenty...