I changed the https to http as bjrosen suggested, but this didn't help. I am using Fedora 15 behind a proxy, and managed to fix it by doing the following in the terminal
#> export http_proxy="h ttp://myproxyaddress:portnumber/"
Also adding the following to the end of /etc/yum.conf
Please excuse the space in h ttp
. This is my first post and the number of links is restricted for new postees, so I added the space to get this through.
Hope this helps