How to solve ---> "http://centos.alt.ru/repository/centos/5/x86_64/repodata/repomd.xml: [Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 403 Forbidden"

For Centos 6:

1. sed -i 's/enabled=1/enabled=0/g' /etc/yum.repos.d/centalt.repo

2. yum clean all