can't install webmin on ubuntu server

I have an Ubuntu server installed and I want to install webmin on it but I can't. I have tried everything but reached no solution. I also set this

deb sarge contrib deb http:// sarge contrib 

in /etc/apt/sources.list. Can someone help me?

Here is the detail of the problem:

t@aksoy:~$ wget --2014-08-18 21:31:47-- Resolving prdownloads.sourceforge.net (prdownloads.sourceforge.net)... failed: Name or service not known. wget: unable to resolve host address ‘prdownloads.sourceforge.net’ 

PS: Sorry for my bad English

1 Answer

Just add

deb sarge contrib 

in your sources.list and run the command

wget -q -O- | sudo apt-key add - 

to import the key
after that

apt-get update apt-get install webmin 

this is a good tutorial at UbuntuHandbook