In RC2 some critical bugs existed.. You can fix these bugs as shown below:

Preparation

Firstly we need to prepare ourselves for the update. This will pull in the new
kernel package too with extra WiFi and NFS support.

sudo apt-get update && sudo apt-get upgrade

Missing Loopback Interface

This affects most networking services, including the Firewall. Please open the /etc/network/interfaces file as the superuser:

gksudo gedit /etc/network/interfaces

You need to append these lines to the end of file and save

# The loopback network interface
auto lo
iface lo inet loopback

Missing Printer Drivers

The cups-driver-gutenprint package wasn’t installed by default. Rectify by issuing the following command

sudo apt-get install cups-driver-gutenprint
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