I installeed 11.2g and when I try login I have got error TNS error adapter. My file tnsname
# tnsnames.ora Network Configuration File: F:\app\Mariano\product\11.2.0\dbhome_1\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.
# This file is actually generated by netca. But if customers choose to
# install "Software Only", this file wont exist and without the native
# authentication, they will not be able to connect to the database on NT.