ORA-12154: TNS:could not resolve service name in sql+ only

A bit of history;
I have a machine (w2k) set up with Oracle 9i that has a database called Prod. The database works perfectly, i can connect to it, make changes and have no issues with it whatsoever. I have now installed Oracle onto a second PC (w2k) and am trying to connect to the database on the original PC. I have set up a database called Prod1 with a host name of the first PC and I can see the database and data. All works well, until this error!

I get this error message when I try to connect to SQL+ on the second pc. I am connected to the database (prod1), can see all information in the database and make changes to it (that appear on both PC's) via Enterprise manager. It is only when trying to launch SQL+ that this message appears.

Here is my tnsnames.ora file, which i cant see any errors with;

# TNSNAMES.ORA Network Configuration File: C:\oracle\ora92\NETWORK\ADMIN\tnsnames.ora # Generated by Oracle configuration tools. PROD1.ORANZ.CO.UK =
  (DESCRIPTION =
    (ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = oranz02)(PORT = 1521))
    )
    (CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = prod)

    )
  )

When i type the following command line into SQL+ - Connect mis_staging/mis_staging_at_PROD1.ORANZ.CO.UK; i get the nasty messge;
ORA-12154: TNS:could not resolve service name.

I am at a complete loss with this. I have only been using Oracle a couple of weeks and we are testing it to see if it is going to work for us in a development capacity. I therefore purchased the media pack but no support with the database and this is proving to be a real nightmare. Please help! Received on Thu Sep 19 2002 - 09:44:21 CDT