The steps mentioned by Jason are very good and should work.
There is a little twist with SQL Developer, though.
The installer installed a start menu shortcut that pointed at a version in the bin directory that simply did not function.
It would ask for a password every time I started SQL Developer, not remember choices I had made and displayed a blank list when I chose TNS as the connection mechanism.
SQLException: [tibcosoftwareinc][Oracle JDBC Driver]BAT3SI was not found in the TNSNAMES. CRYPTO_SEED="qwertyuiopasdfghjkl;zxcvbnm,.s1" BAT1D, BAT1telstra.world= (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = *****corp.telstra.com)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = BAT1telstra.world)(SID_NAME = BAT1D))) Changes need to be updated in TIBCO application end Copy the classess12/opt/tibco/tpcl/5.6/jdbc from /jdbc/lib Add a variable as below in Applications TRA file It also does not have the TNS Directory field in the Database advanced settings referenced in other posts.I tossed the old Start shortcut and installed a shortcut to %ORACLE_HOME%\client_1\sqldeveloper\. but I needed to do this to get SQL Developer to work.Perhaps it was a Win 7 issue as it was a pain to install too.
Search for updating tnsnames:
The cache persists even after SQL Developer has been terminated and restarted.