I have a network in my neighborhood with the same network name as mine but without a password protection. 

What do I have to do to remove this ghost network

@WimB 

If this network belongs to one of your neighbours, you can't do much about it. What you can do is change SSID (network name) of your WiFi network. You can do that in Deco app.

Yes, you will have to configure all your wireless devices to connect to the new WiFi network name, and you may need to make each of your devices Forget old network name, which can be done in device WiFi configuration settings, but this will be one time inconvenience.

If you suspect your neighbour is messing with you and will rename their WiFi network after yours, again, make your WiFi network hidden and then change SSID (network name). You can do that in Deco app, by enabling "Hide this network from WiFi lists." See picture below. Your neighbour won't see your new WiFi network name.

There are ways to see names of hidden WiFi network, but hopefully your neighbour is not that smart.

PS. I am also assuming that this "other network" is not, in fact, your Deco mesh Guest network, which is configured without password by default. Because, if it is, you can just disable it in Deco app WiFi Settings (or make it password protected).

@Alexandre. thanks for your answer, but sorry, I have used some wrong words. Not my real neighbors, the family living next door,  have the same network name, but Deco M4 generates a not password protected network with the same name as my password protected network and everybody could use this network.

I cannot  remove  or I do not know how the remove this non protected network.

WimB wrote

@Alexandre. thanks for your answer, but sorry, I have used some wrong words. Not my real neighbors, the family living next door,  have the same network name, but Deco M4 generates a not password protected network with the same name as my password protected network and everybody could use this network.

I cannot  remove  or I do not know how the remove this non protected network.

You may wish to change your network name anyway, if family living next door run their WiFi with the same network name. Start with that.

Also, check if you have Guest network enabled, in Deco app under WiFi settings, and disable it. See if it fixes the problem.

Finally, how do you know it is your Deco mesh that generates a not password protected network with the same name, and not that other family WiFi router or someone's else?