Can not install Mate Desktop on existing Ubuntu 16.04

Hi,

I am using Ubuntu 16.04 (64bit). I was trying to install mate desktop using following commands :

sudo apt-add-repository ppa:ubuntu-mate-dev/xenial-mate -y
sudo apt update
sudo apt install ubuntu-mate-core ubuntu-mate-desktop -y

The last command failed. Following are the logs snippet

Unpacking libreoffice-common (1:5.1.4-0ubuntu1) ...
dpkg: error processing archive /var/cache/apt/archives/libreoffice-common_1%3a5.1.4-0ubuntu1_all.deb (--unpack):
 unable to open '/usr/share/icons/gnome/256x256/apps/libreoffice-base.png.dpkg-new': Operation not permitted
rmdir: failed to remove '/var/lib/libreoffice/share/prereg/': No such file or directory
rmdir: failed to remove '/var/lib/libreoffice/share/': No such file or directory
rmdir: failed to remove '/var/lib/libreoffice/program/': No such file or directory
rmdir: failed to remove '/var/lib/libreoffice': No such file or directory
rmdir: failed to remove '/var/lib/libreoffice': No such file or directory
...
...
Errors were encountered while processing:
 /var/cache/apt/archives/libreoffice-common_1%3a5.1.4-0ubuntu1_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

I try to install dependencies with
apt-get -f install

But nothing seems to be working.

That PPA will not add Mate to your desktop. That ppa is a upgrade to a already installed mate desktop. Not a way to install Mate.

The Mate packages are located in the Ubuntu repository. So to install Mate to Ubuntu (Unity) 16o4, just install ubuntu-mate-core and ubuntu-mate-desktop without the recommended packages.