Authentication issue in jsonp ria services - asp.net

Question

I am using ria services with jsonp endpoint. When I call my method in service file it works fine in ie and firefox but sometimes works in chrome and sometimes I get "Cross domain javascript callback is not supported in authenticated services." error. Even I dont use authenticated services.
Here is a piece of code about what I have.
Jsonp service
[EnableClientAccess(RequiresSecureEndpoint = false)]
public class PPolJsonService : LinqToEntitiesDomainService<PPolAdvEntities>
{
public IQueryable<QuestionEntity> GetCompleteSurvey()
{
............
}
}
javascript code
function (data) {
var Params = {};
Params.type = 'GET';
Params.url = 'http://127.0.0.1:81/PPolSilverlight-Web-Services-PPolJsonService.svc/JSONP/GetCompleteSurvey;
Params.dataType = 'jsonp';
Params.data = { data:'somedata'};
Params.success = function (data) { };
Params.jsonpCallback = "ppolv2"
$.ajax(Params);
});
In web.config file my setting is <authentication mode="Forms">
İf I set <authentication mode="None"> I am be able to solve all problems with chrome. But the rest of the application needs authentication. So thats why I have to use it as "mode=Forms". And as you see my service does not use authentication so,
Why I am getting this error and is there any solution for it?
Note:
By the way I have other settings in web.config like
<webHttpEndpoint>
<standardEndpoint crossDomainScriptAccessEnabled="true"
automaticFormatSelectionEnabled="true"/>
</webHttpEndpoint>
or these in clientaccesspolicy.xml
<?xml version="1.0" encoding="utf-8"?>
<access-policy>
<cross-domain-access>
<policy>
<allow-from http-request-headers="*">
<domain uri="http://*"/>
<domain uri="https://*" />
</allow-from>
<grant-to>
<resource path="/" include-subpaths="true"/>
</grant-to>
</policy>
</cross-domain-access>
</access-policy>
but none of them is helping me.
Thanks in advance.

Answer 1

Hi Try to add this line to your web.config files. It enables Cross-domain Ajax Requests.
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<system.webServer>
<httpProtocol>
<customHeaders>
<add name="Access-Control-Allow-Origin" value="*" />
</customHeaders>
</httpProtocol>
</system.webServer>
</configuration>

Answer 2

I haven't test it enough but I guess I found a solution.
İf you use secure endpoint in your application and if you don't need to use secure endpoint for jsonp services,
you can add requireSSL="true" in
<authentication mode="Forms">
<forms name=".PPolSilverlight_ASPXAUTH" timeout="2880" requireSSL="true" />
</authentication>
with this small piece of code your unsecure jsonp services will be able to work without authentication.