Error: “ORA-12154: TNS:could not resolve the connect identifier specified”
Solution: This error occurs when oracle cannot find the connection infORMation specified in the tnsnames.ora file. Check the tnsnames.ora file for misspelled connection identifiers or incorrect server names. Ensure that the Oracle Net service name specified in the ODBC connection matches the service name in the tnsnames.ora file.
Error: “ORA-12541: TNS:no listener”
Solution: This error indicates that the Oracle listener service is not running or is not configured properly. Make sure the Oracle listener service is running on the server and listening on the correct port. Check the listener.ora file for correct configuration settings.
Error: “ORA-01017: invalid username/passWord; loGon denied”
Solution: This error occurs when the username or password provided in the ODBC connection is incorrect. Double-check the username and password entered in the ODBC connection settings. Ensure that the user account exists in the Oracle database and has the necessary privileges.
Error: “ORA-12520: TNS:listener could not find available handler for requested type of server”
Solution: This error indicates that the Oracle listener is unable to find a suitable connection handler for the requested type of server. Increase the number of processes or sessions in the Oracle database configuration to allow for more connections. Check the listener.ora file for any restrictions on connection handlers.
Error: “ODBC driver for Oracle is not installed”
Solution: If you encounter this error, it means that the ODBC driver for Oracle is not installed on the system. Download and install the appropriate Oracle ODBC driver for your system from the Oracle WEBsite. Configure the ODBC data source using the installed driver to establish a connection to the Oracle database.