Hello!
I'm using Kubuntu 16.10 with KDE5. And I try to start php-xdebug in the Netbeans IDE and got error-window "KIO error: Error connecting to localhost: access denied".
How to configure this? I have no idea what is happening here.

No idea why netbeans would use KIO, but you're trying to debug with your local host as xdebug server and either xdebug isn't available (running a http server at all?) or it's not enbled for remote hosts or you didn't specify a remote host.
See eg. http://stackoverflow.com/questions/1016 ... -localhost