While trying to open a database connection the following error occurred:
The following error occurred while connecting to "connection name"
ORA-12154 - TNS:could not resolve service name
The sqlnet.ora parameter NAMES.DIRECTORY_PATH was set to ONAMES.
Set the parameter to:
NAMES.DIRECTORY_PATH= (TNSNAMES, ONAMES)
Run Oracle User Wizard on a connection or manual script on the server