I have installed kubuntu 14.04.3 in my laptop, when I check the version of kde its shows as follows,
When I tried
sudo add-apt-repository ppa:neon/kf5 in terminal, am getting response as,
Cannot add PPA: 'ppa:neon/kf5'. Please check that the PPA name or format is correct.
I wish to update kde into Plasma 5. How to solve it ?