Publishing through Portal - "Connection to backend system failed"

Question

We are having a problem publishing documents through our SAP Portalu2019s service u201CPublish Course Contentu201D under Course Administration.
When we go to publish, we get a status u201CConnection to backend system failedu201D with the message u201CNo message availableu201D.
We are running:
Portal on NW 7.0 EhP1, Support Package 04.
ABAP on ERP 6.0, EhP4, Support Package 18.
Both the Portal and ABAP systems are running on Linux RHEL5, with an ORACLE 1.0.2.4 database. 
Portal and ABAP are on different servers.
Not certain if this is significant but under System Configuration, if I open my ABAP back-end systemu2019s configuration and perform connection tests, the overall Connector test fails.
We also have a sandbox system on which we did the configuration first. We have compared all of the values for the configuration we have done to ensure they are configured the same. On the sandbox, the connection test is successful and we can publish content without error.
I have been trying to review the various trace files, increase trace levels, etc. both on the ABAP back-end system and on the Portal. I have been able to find anything that appears significant but this is probably due to my not knowing what to look for.
Which specific trace files should be reviewed for the root cause of the issue? What are the exact steps the Publish process takes to accomplish its work? If we know the exact steps it takes (how it communicates, what modules it uses, what accounts) we might be able to determine the root cause.
We are using a SAML login to our portal for authentication and have removed the Basic password login module from the Authentication Stack u201Cticketu201D. We have established trusted RFCu2019s between the ABAP and Java instances for the Publishing function. When authentication is configured, we try to use the highest form available in the configuration. We use Assertion tickets if available, it not, we use Logon Tickets, if not available, we would then select X.509 certificates and if that were not available, would select Username and password. 
Any ideas as to what we should be looking at would be greatly appreciated. I have searched both SDN and SAPNet for similar situations and not yet found something that corrects the problems.
Thank-you in advance,
Deb Nugent.

Answer 1

Arun,
  Thank-you for your suggestions. The ABAP back-end system is up and I have verified the connection properties. I have had others verify as well. All appears correct.
  The default trace files, through NWA, show the messages:
BackenConfig not correct. processId = 78775D8D1053B855;
 com.sap.hcm.ls.shared.config.backend.BackendConfigException: Destination Exception 
Can not get Destination com.sap.security.core.server.destinations.api.DestinationException: The properties for destination ZZ_LSOCP_JP3 of type RFC could not be located.
I have checked all of the trace files both on the ABAP and Java sides and cannot determine the root cause. I have repeatedly tried things suggested by other threads in SDN and others (consultants) have tried as well. We cannot determine the root cause of the connection errors and now, cannot get the Publishing to work properly.
The only system where the connector test works is our sandbox. Our dev and test systems all fail the connector test. We configured them all using the same documentation.
Is there some way to increase trace levels to try and get more details? And what objects would need to have traces increased?
Deb.