Hi,

What is the oracle database version ? I use oracle data access client tools. Download and Install a 32bit compatible version i.e. files like ODACxxx from oracle website.

Do the following steps.

1) Add TNS_ADMIN windows environment variable and sets its value to <drive>:\app\user\product\version\client_1\Network\Admin

which will reference your TNSnames.ora file.

2) You may have to change TNSNames.ora file entries in 

<drive>:\app\user\product\version\client_1\Network\Admin folder. You can add it like this

<Data store alias> =
   (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.xxx)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = <oracle service name>) 
    )
  )

3) Setup a 32bit ODBC DSN connection ( in case of 64bit windows, it will be in syswow64 folder) and then test it.

Regards,
Naeem