EXP-00056 and ORA-12154

EXP-00056: Oracle error 12154 encountered ORA-12154: TNS: cocould not resolve service name EXP-00000: Export terminated unsuccessfully

Cause: the import or export cannot find the net service name to connect to the database. import and Export connect to the database with the connect information (userid, password, and net service name) that the Rau used to connect. the net service name used by the RAU is in the tnsnames. ora file in the designer Oracle Home (unless a tns_admin registry variable is defined for the designer Oracle Home ).
This error is reported because the tnsname. ora configuration is incorrect and can be reconfigured using the netca tool.