yes i was having trouble with my ESET firewall (new version of nod32), i had the firewall in interactive mode and had allowed all the MCE executable files to have access to all ports, but it wasn't working, switching to automatic mode fixed everything.
now i can update my guide, or rather it updates automatically
try some of the suggestions in here.
http://blogs.msdn.com/astebner/articles/526231.aspx