Hello Fedora Friends users community, I had adjusted and configured my repos.list according to your advice,and got fruitful results. *But please see this,and help me out of the problem*:- [root@localhost ~]# yum upgrade Loaded plugins: aliases, auto-update-debuginfo, changelog, dellsysid, downloadonly, etckeeper, : fastestmirror, filter-data, fs-snapshot, fusioninventory-agent, keys, langpacks, : list-data, local, merge-conf, post-transaction-actions, presto, priorities, : protectbase, ps, puppetverify, refresh-packagekit, refresh-updatesd, remove-with- : leaves, rpm-warm-cache, security, show-leaves, tmprepo, tsflags, upgrade-helper, : verify, versionlock Loading mirror speeds from cached hostfile * fedora: fedora.iitm.ac.in * fedora-debuginfo: ftp.kddilabs.jp * fedora-source: ftp.kddilabs.jp * rpmfusion-free: mirror.cse.iitk.ac.in * rpmfusion-free-debuginfo: mirror.de.leaseweb.net * rpmfusion-free-source: mirror.de.leaseweb.net * rpmfusion-free-updates: mirror.cse.iitk.ac.in * rpmfusion-free-updates-debuginfo: mirror.de.leaseweb.net * rpmfusion-free-updates-source: mirror.de.leaseweb.net * rpmfusion-nonfree: mirror.cse.iitk.ac.in * rpmfusion-nonfree-debuginfo: mirror.de.leaseweb.net * rpmfusion-nonfree-source: mirror.de.leaseweb.net * rpmfusion-nonfree-updates: mirror.cse.iitk.ac.in * rpmfusion-nonfree-updates-debuginfo: mirror.de.leaseweb.net * rpmfusion-nonfree-updates-source: mirror.de.leaseweb.net * updates: fedora.iitm.ac.in * updates-debuginfo: ftp.kddilabs.jp * updates-source: ftp.kddilabs.jp Skipping filters plugin, no data 0 packages excluded due to repository protections Setting up Upgrade Process Resolving Dependencies Skipping filters plugin, no data --> Running transaction check ---> Package firefox.x86_64 0:9.0.1-1.fc16 will be updated ---> Package firefox.x86_64 0:10.0-1.fc16 will be an update ---> Package gstreamer-plugins-bad-free.x86_64 0:0.10.22-2.fc16.1 will be updated ---> Package gstreamer-plugins-bad-free.x86_64 0:0.10.22-2.fc16.2 will be an update ---> Package libvpx.x86_64 0:0.9.7.1-1.fc16 will be updated --> *Processing Dependency: libvpx.so.0()(64bit) for package: libavcodec53-0.9-52.fc16.x86_64* ---> Package libvpx.x86_64 0:1.0.0-1.fc16 will be an update ---> Package xulrunner.x86_64 0:9.0.1-1.fc16 will be updated ---> Package xulrunner.x86_64 0:10.0-1.fc16 will be an update --> Running transaction check ---> Package libvpx.x86_64 0:0.9.7.1-1.fc16 will be updated ---> Package libvpx.x86_64 0:1.0.0-1.fc16 will be an update --> *Processing Dependency: libvpx.so.1()(64bit) for package: gstreamer-plugins-bad-free-0.10.22-2.fc16.2.x86_64* --> *Processing Dependency: libvpx.so.1()(64bit) for package: xulrunner-10.0-1.fc16.x86_64* --> Running transaction check ---> Package firefox.x86_64 0:9.0.1-1.fc16 will be updated *Packages skipped because of dependency problems*: firefox-10.0-1.fc16.x86_64 from updates gstreamer-plugins-bad-free-0.10.22-2.fc16.2.x86_64 from updates libvpx-1.0.0-1.fc16.x86_64 from updates xulrunner-10.0-1.fc16.x86_64 from updates [root@localhost ~]# What are the dependency problems? Is it something to do with libvpx.so.0()(64-bit)? How do I proceed? -Kaushik Guha