Error when running yum commands: 'Cannot retrieve repository metadata (repomd.xml)'

Issue

• When running yum commands errors occur:

[root@computer /]# yum update
Loaded plugins: product-id, rhnplugin, subscription-manager
Updating Red Hat repositories.
Error: Cannot retrieve repository metadata (repomd.xml) for repository: redhat-rhn-satellite-5.5-server-x86_64-6. Please verify its path and try again

[root@computer /]# yum list
Loaded plugins: product-id, rhnplugin, subscription-manager
Updating Red Hat repositories.
Error: Cannot retrieve repository metadata (repomd.xml) for repository: redhat-rhn-satellite-5.5-server-x86_64-6. Please verify its path and try again