giordano@giordano-PORTEGE-M780:~$ sudo ppa-purge ppa:cardapio-team/unstable
[sudo] password di giordano: 
Updating packages lists
W: The repository 'http://ppa.launchpad.net/cardapio-team/unstable/ubuntu xenial Release' does not have a Release file.
E: Failed to fetch http://ppa.launchpad.net/cardapio-team/unstable/ubuntu/dists/xenial/main/binary-amd64/Packages  404  Not Found
E: Impossibile scaricare alcuni file di indice: saranno ignorati o verranno usati quelli vecchi.
Warning:  apt-get update failed for some reason
giordano@giordano-PORTEGE-M780:~$