Resolution:
We have seen this happening many times that the application comes up fine but while uploading the datasource following error is thrown in the eventlog and the elink.log:
ORA-12154: TNS:could not resolve service name
Check the following files if they have the correct values assigned.
1> MqProperties.confg/ConfigValues.xml to have correct values of database, Userid, password, and database name..
2> Check if you are able to connect to database with sqlplus using the details provided in the above file.
3> Check the path set for the $ORACLE_HOME in your environment, for e.g. for JBOSS, check run.bat.