R – Cross Domain policy file forActionscript 3.0

I need to access an ASP.Net2 page from Action Script 3.0 and I wrote the code in .fla file that access the asp.net page but there is a problem in the accessing it reports to me the following error :

Error opening URL 'http://localhost/Trial/Default.aspx'
Error #2044: Unhandled ioError:. text=Error #2032: Stream Error. URL: http://localhost/Trial/Default.aspx
at Script1/sendSQLXML()
at Script1$iinit()

and after searching I found that it is a problem related to Cross Domain policy so I created an XML file called Crossdomain.xml with the following code:

<?xml version="1.0"?>
<!DOCTYPE cross-domain-policy SYSTEM
"http://www.adobe.com/xml/dtds/cross-domain-policy.dtd">


<cross-domain-policy>
    <site-control permitted-cross-domain-policies="all"/>
    <allow-access-from domain="*" secure="false"/>
    <allow-http-request-headers-from domain="*" headers="*" secure="false"/>
</cross-domain-policy>

and i don't know how to use it from ACS3 and where to put it
Note: i run the Asp.Net2 page in the IIS