sudo apt update && sudo apt upgrade
[sudo] password for freddish:
Get:1 http://security.ubuntu.com/ubuntu yakkety-security InRelease [102 kB]
Ign:2 http://ppa.launchpad.net/noobslab/themes/ubuntu yakkety InRelease
Hit:3 http://archive.ubuntu.com/ubuntu yakkety InRelease
Hit:4 http://archive.canonical.com/ubuntu yakkety InRelease
Get:5 http://archive.ubuntu.com/ubuntu yakkety-updates InRelease [102 kB]
Err:6 http://ppa.launchpad.net/noobslab/themes/ubuntu yakkety Release
  404  Not Found
Hit:7 http://repository.spotify.com stable InRelease
Get:8 http://archive.ubuntu.com/ubuntu yakkety-backports InRelease [102 kB]
Hit:9 https://deb.opera.com/opera-stable stable InRelease
Get:10 http://security.ubuntu.com/ubuntu yakkety-security/multiverse amd64 DEP-11 Metadata [212 B]
Get:11 http://security.ubuntu.com/ubuntu yakkety-security/main amd64 Packages [80,4 kB]
Get:12 http://security.ubuntu.com/ubuntu yakkety-security/main i386 Packages [78,7 kB]
Get:13 http://archive.ubuntu.com/ubuntu yakkety-updates/multiverse amd64 DEP-11 Metadata [212 B]
Get:14 http://security.ubuntu.com/ubuntu yakkety-security/main amd64 DEP-11 Metadata [8 272 B]
Get:15 http://security.ubuntu.com/ubuntu yakkety-security/universe i386 Packages [27,4 kB]
Get:16 http://security.ubuntu.com/ubuntu yakkety-security/universe amd64 Packages [29,7 kB]
Get:17 http://security.ubuntu.com/ubuntu yakkety-security/universe amd64 DEP-11 Metadata [2 188 B]
Get:18 http://archive.ubuntu.com/ubuntu yakkety-updates/main i386 Packages [149 kB]
Get:19 http://archive.ubuntu.com/ubuntu yakkety-updates/main amd64 Packages [151 kB]
Get:20 http://archive.ubuntu.com/ubuntu yakkety-updates/main amd64 DEP-11 Metadata [111 kB]
Get:21 http://archive.ubuntu.com/ubuntu yakkety-updates/main DEP-11 64x64 Icons [55,8 kB]
Get:22 http://archive.ubuntu.com/ubuntu yakkety-updates/universe amd64 Packages [81,1 kB]
Get:23 http://archive.ubuntu.com/ubuntu yakkety-updates/universe i386 Packages [78,7 kB]
Get:24 http://archive.ubuntu.com/ubuntu yakkety-updates/universe amd64 DEP-11 Metadata [83,6 kB]
Get:25 http://archive.ubuntu.com/ubuntu yakkety-updates/universe DEP-11 64x64 Icons [94,2 kB]
Get:26 http://archive.ubuntu.com/ubuntu yakkety-backports/multiverse amd64 DEP-11 Metadata [216 B]
Get:27 http://archive.ubuntu.com/ubuntu yakkety-backports/main amd64 DEP-11 Metadata [212 B]
Get:28 http://archive.ubuntu.com/ubuntu yakkety-backports/universe amd64 DEP-11 Metadata [216 B]
Reading package lists... Done
N: Ignoring file '20auto-upgrades.ucf-dist' in directory '/etc/apt/apt.conf.d/' as it has an invalid filename extension
E: The repository 'http://ppa.launchpad.net/noobslab/themes/ubuntu yakkety Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
freddish@MainBrain:~$