@Skarbo The Deco M9 plus and RE305 cannot build up a mesh network together, but they can work together. The RE305 can connect to the Deco M9 plus to boost wifi signal even though it is not the same...

@antythesis Thanks for your reply. Was there any power outage during the firmware upgrading? You mentioned that you can detect the wifi network name of the RE305, have you ever tried to refresh the...

@bk93 Hello, you can enable Access Control on the Archer A2300 and add the WAN MAC of the second router into blacklist. Then the router and the devices behind it won't be able to access internet....

@Lancing The same post. https://community.tp-link.com/en/home/forum/topic/197688?replyId=414954

@Lancing Thanks for your valued reply. Could you please show us the screenshot of the link aggregation settings page on the QNAP NAS? And what about the OS version of the three Windows 10 machines?...

@Sanders2222 In client mode, the TL-WR802N will connect to the main router by wireless, and your computer can access internet from it by wired cable. Like main router )))(((802N(client mode)---PC....