Dear Biswajit
I hope you are well and many thanks for using the SAP Discussion Forums 
.
Now in relation to the scenario that you have described you mentioned the following:
- You have the UWL implemented in your SAP EP 7.31 portal.
- It fetches work items from a back end system which is connected by a RFC destination.
- It is seen that users have to hit the refresh button in UWL more than once to get the actual list.
Now regarding the exception you are recieving we can clearly see the following:
- connectivity.destinations.PortalDestinationsServiceException: Could not get connection for alias PXXCLNTXXX. Contact your system administrator.
Based on this exception there are several avenues of analysis that we can follow:
In scenarios like this when we see such a message what may be causing it is a misconfiguration/misalignment with regards to the UWL and destination setups.
Kindly view and implement the following note:
SAP Note 1133821 - UWL Destination Service Configuration
In addition to the possibility of a misconfiguratin we can also consider checking the system alias and the connector setups themselves.Kindly implement the note number outlined above and also view the two documentation links provided below as they provide a detailed overview on the correct settings and configurations.
- Check that after applying Note 1133821 the destination names and the UWL connector names exactly match, even considering case-sensitiveness. If your portal system alias (=UWL connector name) is for example XYZCLNT100, then the rfc destination name should be exactly XYZCLNT100$WebFlowConnector. Please correct the rfc destination accordingly. (If Required)
1: If you make changes kindly restart the Portal Cluster
2: Clear the UWL Cache/Restart the UWL service
Now retest, are you still encountering the issue?
Kindly update me as per your findings.
I greatly appreciate your time and patience and I look forward to recieving your reply.
Kind Regards
Troy Cronin - Enterprise Portal Support Engineer