Knetworkmanager problems, can't see wifi[SOLVED]

[Darkanima]

Well I've got some problems with Knetworkmanager. I used to connect to Wifi with it when I'm not at home, but they have dissapeared and only shows wired networks. I've tried to reinstall, remove and install,... but the problem remains. Now I'm using Kwifimanager, but i don't like it. Do you know a solution for this?

Thanks in advance.

A Screenshot of the problem:

PD: I've solved commenting all the lines in /etc/network/interfaces and restarting.