@PTrenholme: That was my first reaction. But I noticed that Safaa was not trying to use redhat paid support methods, instead was attempting to use the free fedora
enterprise (EPEL) repo which is designed just for this use. There is no compulsion to use RHEL with the paid support option - the message probably means that RHN repos are still enabled - that's all.
The error message of interest is:
Hmmm... that is a urlopen error - if that stuff in the brackets is a url, shouldn't it have forward
slashes? Looking more closely: it seems to be French, saying there is "no way for d'acc\xc3\xa8s to access l'h\xc3\xb4te target" But I don't know what it is referring to. If I think d'acc means "account" then this message may mean that the computer is on a managed network and OP is not sysadmin? (eg. the network policy is not letting this computer connect to the repo url.) But that's a guess.
Try pinging the mirrorlist url?
Clean the yum cache, check the repo configuration, check the route etc.
It is also possible to set yum to use the core repo instead of going via the mirror list.
eg. follow advise in link, post #2
Of course - just not using epel-testing will work too.