hi there: I am trying to use yum to update my FC4 system, but didn't succeed! looks like it is because I am behind a firewall, I need proxy to access outside web, and maybe an MS proxy, is there any ways to use yum behind a such proxy? how do I know what kind of proxy I am behind? I export https_proxy with username and passwd but the following error occured. actually I tried a few formats of setting this env variable, I am not sure I setup correct or not. my corporate proxy need a user name and passwd, in user name there is a +space+ " " in my user name. so could any one tell me exactly which variable and how to and where to set it? ----------------------------------------------------------- [root@zhufedora ~]# yum update Repository livna-testing is listed more than once in the configuration Setting up Update Process Setting up repositories livna-stab: ###### 1/8Cannot open/read repomd.xml file for repos itory: livna-stable failure: repodata/repomd.xml from livna-stable: [Errno 256] No more mirrors to try. Error: failure: repodata/repomd.xml from livna-stable: [Errno 256] No more mirrors to try. [root@zhufedora ~]# ----------------------------------------------------------- any clues? I know our company may have strict firewall than others. I heard only port 8080 is opened. thank you! Houxiang