I have one external modem (Intex) to connect to the internet in my laptop. I have Ubuntu 12.04

Screenshot from 2012-08-30 08:09:39.png

Every-time that I try to connect it asks for my administrative password 3 times! And again when I disconnect!

Screenshot from 2012-08-30 08:11:18.png

Please can someone help me my fingers are becoming tired