Unable to install package from ubuntu software center in 11.04

[avinash-1]

hello i am registered ubuntu user my id is # 34195..i am unable to install any package from software center in 11.04..it show thae message package is from untrusted source ..please help me

[dino99]

how i install ubuntu:

http://ubuntuforums.org/showpost.php?p=10161428&postcount=2

for updating:

sudo apt-get install synaptic
sudo synaptic

have you set non genuine repo to get these "untrusted" warning ?