Error attempting to view objects in DB Explorer: "ORA-12571: TNS: packet writer failure". Or there are no objects listed in DB Explorer.
* "Use OCI v7" option is checked.
* Oracle Client version installed is not version 8.1.7 or above.
Remove the OCI v7 option in the connection window:
1. Select View | Preferences menu option.
2. Select Session and uncheck "Use OCI v7" checkbox.
3. Close SQL Nav and re-login to database and re-test the issue.
Ensure the following:
* The Oracle client version installed on the machine is at least version 8.1.7 or above as SQL Navigator is not compatible with any version below 8.1.7.
* The installed Oracle Client is a 32-bit version.