Three possible causes I can think of off the top of my head:1) Your software firewall is preventing localhost loopback.2) Your NIC or software protocol adapter doesn't support localhost proxying.3) Your computer doesn't know how to reach the host "localhost". Try making a localhost entry in your hosts file.C:\windows\system32\drivers\etc\hosts There should be an uncommented entry that says: 127.0.0.1 localhost