RESOLUTION 1:
1. Go to Control Panel | System | click “Advanced System Settings”.
2. Under ‘Advance’ tab, click ‘Environmental Variables’ button.
3. Under ‘System Variables’ list (bottom half), scroll down to ‘TNS_ADMIN’.
a. If ‘TNS_ADMIN’ does not exist, select ‘NEW’ button, enter the following, and click OK:
Variable Name: TNS_ADMIN
Variable Value: enter the location path to where your ‘tnsnames.ora’ file is located
b. If ‘TNS_ADMIN’ exist, click ‘Edit’ and enter the correct location path (to your ‘tnsnames.ora’ file) in the Value field
RESOLUTION 2:
Place a valid ‘tnsnames.ora’ file in the location specified in the ‘TNS_ADMIN’ variable OR the %Oracle Home%\network\admin folder.
The usual default location for the ‘tnsnames.ora’ file is:
11g: C:\app\<YOUR_USER>\product\11.2.0\client_1\NETWORK\ADMIN\
12c: C:\app\client\<YOUR_USER>\product\12.1.0\client_1\NETWORK\ADMIN\
RESOLUTION 3:
Uninstall SQL Navigator and reinstall into a folder outside the C:\Program Files(x86) folder. e.g C:\Quest Software folder.
STATUS:
Waiting for fix to be released in a future version of SQL Navigator for Oracle.
