I made a clean installation of Fedora 11 but yum either fails to update or the updates take so long i have to abandon them usually after a full night without progress.

These are contents offedora.repo :-

[fedora]
name=Fedora $releasever - $basearch
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=fedora-$releasever&arch=$basearch
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY

[fedora-debuginfo]
name=Fedora $releasever - $basearch - Debug
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=fedora-debug-$releasever&arch=$basearch
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY

[fedora-source]
name=Fedora $releasever - Source
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=fedora-source-$releasever&arch=$basearch
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KE
~
~

From that PC that is having the problems are you able to navigate to any of the mirrors listed?

For example http://mirrors.fedoraproject.org/mirrorlist?repo=fedora-$releasever&arch=$basearch seen as this is the only one enabled above.

If not, it could be DNS. So are you able to ping domain names?

Edit:
You don't mention if this is 32bit or 64bit but here is a 32bit repo

http://mirrors.fedoraproject.org/mir...a-11&arch=i386