When hosting a WCF web service remember to set up a client
access policy file. As a Silverlight
call will require this file for security purposes. In iis you just need to add it to the root folder of
the web site.
Example File
<?xml version="1.0" encoding="utf-8"?>
<access-policy>
<cross-domain-access>
<policy>
<allow-from http-request-headers="*">
<domain uri="*"/>
</allow-from>
<grant-to>
<resource path="/" include-subpaths="true"/>
</grant-to>
</policy>
</cross-domain-access>
</access-policy>
File Name: ClientAccessPolicy.xml