Q: My Application just shuts down or won't start?
A: Remember that the ListenerProxy object communicates with the UltraPort Listener over TCP/IP. This can trigger DEP or be blocked by firewalls and network security programs (like Norton's or Symantec's). The most common experience is with users on Microsoft Windows Server 2003 or greater who have DEP blocking all applications by default.
Q: The UltraPort Listener will not forward my application any messages. What am I doing wrong?
A: First verify that the listener profile settings are correct (see the online help for the UltraPort Listener). Second, verify that there are messages waiting to be sent to your proxy. Do this by examining the HL7 Data Folder (in the UltraPort Listener profile) to verify that there are files with a ( .pq ) file extension. These are 'Proxy Queue' messages. If there are no files there, then there are no messages waiting to be sent to your proxy. Third, verify that there is nothing blocking the connection between the UltraPort listener and your proxy application like a firewall or network security system. To get immediate feedback stop the UltraPort Listener Windows service and run the listener profiles locally (click here). You should be able to see the errors occurring in the event tracelog of the immediate window.
Q: I am being sent a corrupted message of some kind, I set the SendThisAcknowledgement property to False, how can I remove the message from the Ultraport Listener proxy message queue so that it will stop sending me the same message over and over again?
A: Do this by examining the HL7 Data Folder (in the UltraPort Listener profile) to verify that there are files with a ( .pq ) file extension. These are 'Proxy Queue' messages. If you sort the files in Windows Explorer by the Last Modified date then the offending message should be the topmost one with a ( .pq ) file extension.
Q: Can my Proxy application receive HL7 messages from more than one UltraPort Listener on the same port?
A: Absolutely. You can configure multiple UltraPort listener profiles to forward messages to the same Proxy application. You can also have different servers running the UltraPort listener forward messages to your single Proxy Application.
Q: Can my Proxy application receive HL7 messages on multiple ports?
A: Absolutely. To do this you would need to create multiple ListenerProxy objects and call the StartListening() method on each with a different port number.
Q: How can I tell if my Proxy Application is up and running and listening for HL7 messages?
A: You can use the 'Test' button in the Optional Listener Settings (Proxy Settings) of the UltraPort Listener configuration program. When you click that button, the UltraPort program will perform a built-in Call/Response to the proxy application. This is all handled internally by the ListenerProxy object. The only interface to you is that you will see a ConnectionAccepted event (when the UltraPort Listener connects to your program) immediately followed by a ConnectionDropped event (your object will automatically reply to the test and the UltraPort Listener will close/drop the connection). See Below.
Proxy Settings in an UltraPort HL7 Listener Profile