Xubuntu can’t set up custom network settings via /etc/network/interfaces file

To fix remove network-manager

 sudo apt-get remove network-manager wicd -y

and set up your settings into 'interfaces' file

sudo vi /etc/network/interfaces

auto lo
iface lo inet loopback
iface eth0 inet static
address 10.0.0.137
netmask 255.255.255.0
gateway 10.0.0.2
auto eth0

Don't forget about /etc/resolv.conf… Read the rest