Hi 

I'm integrating client's website with SIM version and some of the transactions are failing at relay response. Not all transactions are fialing. Some are going through OK and some are failing. The transactions are being approved by Authorize.Net but when it sends a relay response it fails sometimes. I'm using ASP.NET HTTP handler file(.ashx) as a relay response URL. So whenever a request is made to this type of webpage, handler references another page that produces a specified code which is sent to the visiting browser. 

My client is using same merchant account for two different websites. Can we use a same account for two different website?

If I'm sending a relay response URL in a  x_relay_URL with in a POST transaction in with x_relay_response as TRUE and x_relay_always as TRUE, do I also need to add Response/Receipt URL's in a merchant interface as well. If yes, then how could I add two default receipt link URL's because I'm using same account for two different website and both websites have diffrerent relay response or receipt URL's

Please let me know if any mre information is required from myside to resolve this issue. Also, could someone help me as soon as possible because the issue is happening on production environment

Many Thanks

Sarab