@SadSam Hi, does ER8411 work fine before? Did you have any VLAN settings? Actually, what is your network layout? Can this windows PC access internet normally? If other devices can not obtain a IP...

@WolframDV Yeap, you can. The POE port would be a normal ethernet port when you plug a non-PD into it.

@stringy I guess the amazon echo dots can only work with 2.4G wifi, have you tried creating a single separate 2.4G wifi for it for testing? Only enable 2.4G, no 5G.

@Eadeco What's the firmware version of your controller? I can see it in mine, check here:

@Sahedul Hi, so you mean this issue occurs after you upgrade ER605 firmware to 2.1.1? Actually, what is the issue exactly? Can you type it more?

@candre Uhm...maybe you can forget the EAP on the controller, and upgrade them to the 5.1.0 in standalone mode then manage them by controller again. But note Forget means reset, so it is up to you,...