@Kaido 

Hello，

Thanks for your reply, we will do some troubleshooting first and try to fix it.

1. Are you able to see the 2.4G wifi network name of your router?

2. Try to change the authentication type and encryption type of 2.4GHz to auto on the main router and then reconfigure the RE205.

At this time,  when you reset the range extender, please check if you can see all lights flashing once on the RE205.

Please try different methods to set up it.

3. Meanwhile, is there any mac filtering or access control enabled on the main router?

4. Still the same, please log in to the web UI of the RE205 and take a full screenshot of the status page, and then go to settings-system tools-system log to save it and send the txt file to us. And please tell us the model number of your main router. 

Here is a link you can refer to access to the web UI of RE205:

https://www.tp-link.com/en/support/faq/1398/

Thanks in advance, and have a nice day. 

@Kaido 

Hello，

I have checked your settings. From the picture, the issue may be that the 2.4G network of your home wifi didn't have a signal.

In this case, the range extender can't get the Internet from your router on 2.4G.

So you need to enable the 2.4G network on your router, then try to reset and reconfigure the range extender again.

Hope it can help and have a nice day!

@Kaido 

Hello, 

For this case, since the status page shows that your main 2.4G wifi has no signal, and range extender broadcast the wifi signal from the router, so we have nothing to do on the range extender side.

If you don't know how to configure your main wifi, you can try to contact your router's support to check 2.4G of your router, then also try to change a different channel of 2.4G.

After you finish the configuration of the router, please try to reset and reconfigure the range extender again, thank you!

Have a nice day!