tns

السلام عليكم ورحمة الله وبركاته
i have installed oracle 9i database and forms 6i after installation i made changes with the following file tnsnames.ora and it is located in the following path :c:\orant\net80\admin
i added the following text at the end of the file:
LADIES=
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = SBIT2031)(PORT = 1521))
)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = ladies)
)
)
befor 2 or 3 months the form builder was working good and i have made forms and it was working but sme changes happened to my pc (installing software related to oracle) so it is not working any more and each time i open forms builder and try to connect it gives me the following message:
ora-12203:TNS: unable to connect to destination

would you please help as soon as possible.