Interface Problem --newbee

This is my first effort to use WS and the intent is to monitor my own traffic as per the instructions in the “Port Forwarding” tutorial for beginners use of WS. Using Ubuntu 10.04 (current version) the interface screen of Wireshark does not show any active interface. Using the dual boot capacity of the same computer and Windows 7 the interface screen brings up two items: one labelled microsoft and another with an ip that looks like the internet ip of the Ubuntu system. The Windows WS program is a current download and the Ubuntu WS program is the 1.2 version for Linux provided in the Ubuntu program. I do not understand the reason for the difference in identifying interfaces or how to rectify this problem. I strongly prefer to use the Linux system if at all possible. All friendly comment on this will be appreciated.

No interface or no active interface ?

Try to launch wireshark as root.
Using sudo or su or …

Olivier