The system network service is not compatible with this version ...Error solution(Ubuntu)

Check out by the command ifconfig whether what output you get.
If you are facing the problem there are chances you might not get the ip address in the output. For the naive people, in simpler words the output will be just one para and not 2 as it should be.
Try this link
http://pratiklahoti.wordpress.com/2012/06/26/ubuntu-12-04-the-system-network-services-are-not-compatible-with-this-version/

For me this link didn't work but for many the above link worked so try that out first.

My experiment:
1. sudo  vi /etc/network/interfaces
you will see the lines:
auto eth0
iface eth0 inet dhcp

instead type:
auto eth0
iface eth0 inet static

address 192.168.1.5
netmask 255.255.255.0
gateway 192.168.1.1

Now do:
2. sudo nano /etc/resolv.conf
Paste below lines:
nameserver 127.0.0.1
nameserver 192.168.1.1

now restart your network with:
3.sudo /etc/init.d/networking restart

now check
4.ifconfig

5.ping joindiaspora.com
If this gives response, your net is working ....Hurray!

6.sudo service network-manager restart

This is basically called static ip.

Let me know whether it works or else what error u get take a screenshot and mail me.