This is a follow-up to Wenlong Dong'g blog, How to use WSDualHttpBinding for Hosted Services .
In an Internet scenario valid HTTP requests and responses only travel in one direction, HTTP is designed as a one-way protocol. When using the WSDualHttpBinding WCF therefore creates a seperate HTTP channel for callbacks.
To enable the service callback, you have to add the clientbase address as mentioned by wenlong.
But then you also have to register the address namespace, in windows xp and server 2003,you will have had to use the httpcfg utility, but in recent versions of windows you have to use netsh as shown below
netsh http add urlacl url=http://+:80/MyUri user=DOMAIN\user
e.g netsh http add urlacl url=http://+:2040/clientbaseaddress user=Users
i hope this helps
