IIS7 No response; In Fiddler2: "readresponse() failed for POST requests to a host IP which is not local. In Failed Request Tracing error in ManagedPipelineHandler with “The I/O operation has been aborted because of either a thread exit or an application request. (0x800703e3)”

 

Just spent 10 hours trying to figure out why a WorldPay callback to my development machine was not working.

This was simply because I had “Email scanning” protection enabled in AVG Antivirus.  If you turn this OFF, everything will work fine.

This is related to the Stack Overflow post: http://stackoverflow.com/questions/7439063/iis-asp-net-website-managedpipelinehandler-error-an-operation-was-attempted