OUTPUT:
shamrock% oerr ORA 12154
12154, 00000, "TNS:could not resolve service name"
// *Cause: The service name specified is not defined correctly in the
// TNSNAMES.ORA file.
// *Action: Make the following checks and correct the error:
// - Verify that a TNSNAMES.ORA file exists and is in the proper
// place and accessible. See the operating system specific manual
// for details on the required name and location.
// - Check to see that the service name exists in one of the
// TNSNAMES.ORA files and add it if necessary.
// - Make sure there are no syntax errors anywhere in the file.
// Particularly look for unmatched parentheses or stray characters.
// Any error in a TNSNAMES.ORA file makes it unusable. See
// Chapter 4 in the SQL*Net V2 Administrator's Guide. If
// possible, regenerate the configuration files using the Oracle
// Network Manager.


I've found that if you use the IP of the server you are trying to connect to instead of the NAME you get less errors. Have you tried that?

So instead of sometyhing like: (HOST = calistoga)
You would insert the IP like: (HOST = 129.50.6.9)

- Magnus