I have installed Oracle Instant Client 10 so I can create a new ODBC connection to a 10G server (currently using Oracle 9 ODBC drivers for other apps). I am in ODBC Data Source Administrator > System DNS > clicking add...I select my new Oracle 10 Instant Client Driver, click finish. The problem is: I am not able to select a TNS name from the drop down box. If I click the drop down box there are 4 options that look like greek characters. I should have my prod,test environments like I do for the Oracle 9 ODBC connection. I changed my system variables to include the path where my Instant Client 10 was installed (which has a copy of tnsnames.ora file). This fixed some errors I was having before this one but I still cannot select my prod environment with this new driver.