I'm getting the attached error message when trying to run a Silverlight application. The applications appears to get this error every time it tries to access a web service from an ArcGIS Server 10.4 install. I have a ArcGIS Server 10.3.1 and ArcGIS Server 10.0 install and accessing web services from those instances work fine, but if I include a web service from the ArcGIS Server 10.4 install I get the attached error message.
I have followed the instructions for including the crossdomain.xml and clientaccesspolicy.xml files in the root of the web server, but I still get the error message.
Thanks for any help!