In the documentation, it says that add/remove software is use only to install from CD drive[1]. However this program refuse to run when no internet connection, why not just prompt for the installation media? assuming everybody has fast internet connection was too optimistic. 1. So what is the correct way to install/remove software after the installation (using GUI)? 2. In /etc/yum.repos.d/CentOS-Media.repo the sample command was incorect, it should be --enablerepo=c5-media. But anyway, it still did not works here, centos cd was mounted under /media/CentOS_5.0_Final, after manually changed (is there any shortcut, ie using old good /dev/cdrom ?) : [root at localhost yum.repos.d]# yum --disablerepo=\* --enablerepo=c5-media install tftp Loading "installonlyn" plugin Setting up Install Process Setting up repositories Reading repository metadata in from local files Parsing package install arguments Resolving Dependencies --> Populating transaction set with selected packages. Please wait. ---> Downloading header for tftp to pack into transaction set. media://1176235114.525559%235/CentOS/tftp-0.42-3.1.el5.centos.i386.rpm: [Errno 4] IOError: <urlopen error unknown url type: media> Trying other mirror. Error: failed to retrieve CentOS/tftp-0.42-3.1.el5.centos.i386.rpm from c5-media error was [Errno 4] IOError: <urlopen error unknown url type: media> Also i feel that yum is to slow even when running from cache, ymmv. 3. What is the program/service responsible to automatically display media in desktop when mounted? Thanks! --beast [1] http://www.centos.org/docs/5/html/yum/sn-software-management-tools.html