I am using the LinkPointTransaction.dll from FirstData to process credit card transactions. As the code is running, a call to the LinkPointTransaction.LinkPointTxn.Send() sends the transaction successfully to FirstData over the internet, but my application crashes w3wp.exe somewhere during that call, before it hits the next line. It does not throw a managed exception that I can see; it just crashes. The problem is it works fine when I run it on VS development server. After some research I found that when I recycle the ApplicationPool, the first time I try to access the application, it fails [basically ends the w3wp.exe process]. And then the w3wp.exe is restarted. From here on the application works for sometime and fails again eventually. So anyone have any idea whats going on??