security sandbox on air

I am using Flex 4.6 with AIR SDK 3.6 in Flash Builder 4.7 to develop desktop AIR application. I am trying to implement the Worker (embed in code) that will check for valid URL. For this purpose I am using URLRequest. This worker is automatically compiled into SWF by FB 4.7. But during runtime I am receiving following error message on URLRequest:

Error #3205: Only application-sandbox content can access this feature.

Is there any work around to this?