HTTP Request Error need help ASAP!

SO i have two services running on a newly install of ArcgIS server 10.1 running on Windows Server 2012.

I have built an application with the Flex Application builder using both services. The application works fine from the server. However, if i try to access the application from outside the server it loads to the point of loading the first service and i get this error:

Map Manager error

AIA Basic Web layer failed to load: Fault code:
Server.Error.Request

Fault info: HTTP request error

Fault details: Error: [IOErrorEvent type="ioError"
bubbles=false cancelable=false eventPhase=2 text="Error #2302"]. URL: http://preservationsearchwebgis.anth...pserver?f=json

I have read the forums and seen possible solutions of the crossdomain file which it is unclear for me what syntax i would need for the file.

I have seen an issue of the service output directory i initially tried changing this but not sure if I changed it to the right place so no solution there yet.

my application is at:

http://preservationsearchwebgis.anth...ers/AIAWebGIS/

Can anyone suggest an answer with example of syntax or where i need to put the proper files?

Thank you in advance for your help.

Tim Goddard.