Can't change ethernet card's IP address

Question

I have Ubuntu 12.10 desktop version installed on HP 4000 PC, when I try to set up static IP address for NIC by using Network from menu bar, and switch from DHCP to manual, I can add static IP, default gateway and network mask. However the Save button has been grayed out. So I can't set up static IP address for the NIC. Can anybody give me some explanations?

Thanks for your help.

Answer 1

Try following this guide to change the IP manually, that will usually do the trick:

http://wiki.debian.org/NetworkConfiguration#Configuring_the_interface_manually

Regards, Stefan.