@md_himelali_18 That's up to a TP-Link decision whether to modify the FW or not. I'm pretty sure that some features are limited in range-extender mode as well as in AP mode - details.

@henryzusa I've meant to swap the ports on the linksys switch where WR840 and Archer A6 cables are connected to exclude a potential linksys switch port issue. Let's hope a new FW release will be...

@Vvet Make sure that your child devices are not using a randomized MAC addresses - details. If this issue has been observed after FW upgrade (it was working fine with the old FW version) you can...

henryzusa wrote @terziyski One other cable goes to the upper floor to a LinkSys that has 3 cables connected: One for other TV decoder, one for the TL-WR840N and one for the Archer A6...

@Bradscopegems If you're refering to a PLC device they should be on the same power curcuit - refer this FAQ for more details on these devices. The other possible options are: 1. Installing a range...

@Melissa_91 You can use a range extender to expand further your wireless coverage. Other option is to use another router in AP mode which involves cabling.