@blommethomas First of all, put fixed ip on the controller,eg 192.168.4.2/24 i see many people use dynamic ip on it and that can cause problems. And before you adopt the router, log on to the...

@knightmare yes, there are slightly different terms for stand alone and controller mode. in controller mode it's port forwarding, why I don't know.

@knightmare I dont use standalone myself but look at 2.2 Configuring the Virtual Servers

@knightmare if you look in the documentation for the product, you will find the answer https://static.tp-link.com/upload/manual/2023/202311/20231116/1910013557_ER8411(UN)_UG.pdf

@Ric04jan72 You have focused on the gateway, I am quite sure that the problem does not lie there, what you have not said anything about is which access points and switches you have. are there many...

@spd2612 vlan1 can only changed IP, all other change to whatever you want