Hi I am behind a two proxy server, one requires authentication and is fast, other slow but requires no authentication. Can someone tell me how to configure yum to work with the first one. I am using FC4. on doing [root@spsingh sumeet]# yum update You have enabled checking of packages via GPG keys. This is a good thing. However, you do not have any GPG public keys installed. You need to download the keys for packages you wish to install and install them. You can do that by running the command: rpm --import public.gpg.key Alternatively you can specify the url to the key you would like to use for a repository in the 'gpgkey' option in a repository section and yum will install it for you. For more information contact your distribution or package provider. I tried it on the latter and tried to install keys using [root@spsingh sumeet]# rpm --import http://dag.wieers.com/packages/RPM-GPG-KEY.dag.txt error: http://dag.wieers.com/packages/RPM-GPG-KEY.dag.txt: import read failed(-1). rpmk: url.c:103: XurlFree: Assertion `u && u->magic == 0xd00b1ed0' failed. Aborted Please help Also, The second proxy is on ipv6