How to resolve TNS error in Oracle when using an ODBC DSN
Make sure that your tns files (tnsnames.ora, sqlnet.ora) are in a certain directory that is readable by all users.  for example &quot;/oracle/network/admin/&quot;
Make sure that all your users and processes that need to work with the database[s] have the environt variable TNS_ADMIN defined with the value &quot;/oracle/network/admin/&quot;.
Doing so gives a good chance that all processes look to the same configuration.