ORACLE 11G EXPRESS EDITION
ERROR OCCURED ON RETRIEVING DATA XML
You need to find what is erroring.
Under OAS, go to admin -> manage bi publisher -> Data sources
-Use the "test" button on your failing data source. Confirm it still fails.
If its still failing go to the weblogic console to investigate the source:
http://myserver:port/console
Go to: Services -> Data Source
Open the data source and test it. If it fails fix it.
Either of these tests should yield you a better error with more details.