kamalakant@kamalakant-lenovo:~$ sudo ppa-purge ppa:asukhovatkin/unity-launcher-folders
Updating packages lists
W: GPG error: http://ppa.launchpad.net/atareao/atareao/ubuntu xenial InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6A9653F936FD5529
W: The repository 'http://ppa.launchpad.net/atareao/atareao/ubuntu xenial InRelease' is not signed.
W: The repository 'http://ppa.launchpad.net/asukhovatkin/unity-launcher-folders/ubuntu xenial Release' does not have a Release file.
E: Failed to fetch http://ppa.launchpad.net/asukhovatkin/unity-launcher-folders/ubuntu/dists/xenial/main/binary-amd64/Packages  404  Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
Warning:  apt-get update failed for some reason
kamalakant@kamalakant-lenovo:~$