ken wrote: <snip> > Then I found and read > http://wiki.centos.org/AdditionalResources/Repositories?action=show&redirect=Repositories. as stated on that page, mixing 3rd party repos does not always work so well. Your problem is an example of what can go wrong. > > Moreover, after erasing my installed libdvdread, I did: > # yum install libdvdread > .... > ================================================================================ > Package Arch Version Repository > Size > ================================================================================ > Installing: > libdvdread i386 4.1.3-1.el5 epel <snip> > Isn't epel pretty much a standard repository? epel is one of the big 3rd party repos, rpmforge is another. you are installing libdvdread from epel and trying to install gstreamer-plugins-ugly from rpmforge. Unfortunately the former doesn't have the right lib version for the latter. One solution would be to give higher priority to rpmforge over epel. Then uninstall [the epel] libdvdread, and yum install gstreamer-plugins-ugly should properly pull in the rpmforge libdvdread.