I have 2 different applications, one of a C# WinForms app that is directly referencing the AuthorizeNet.dll and we are collecting credit card information in the app and sending it to Authorize.Net using that dll. I'm not sure what that integration method is called. The other application (because the first one is not PCI compliant) is using the SIM, we post some user information to Authorize.Net and the user enters credit card information there. We've set up to recieve silent posts when transactions are complete and we do as long as the transaction is approved, if it's not approved we don't get anything. However, that only applies to the website where we have redirected the user to Authorize.Net's website. The WinForms app gets the silent post on both accepted and declined transactions.
To recap, the application using the C# SDK gets the silent post on both accepted and declined transactions. The website using the SIM gets the silent post when the transaction is accepted but not when it's declined.
Thanks.