I have a ORA-06401 NETCMN: invalid driver designator problem - on Windows 2000 - the network databases work correctly, but the local one doesn't any way, and keeps givig me this message.
My tnsnames.ora looks like this:

# C:\ORANT\NET80\ADMIN\TNSNAMES.ORA Configuration File:C:\orant\net80\admin\tnsnames.ora
# Generated by Oracle Net8 Assistant

PROD.WORLD =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.73.61)(PORT = 1526))
(CONNECT_DATA = (SID = apmc))
)

TEST.WORLD =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.73.62)(PORT = 1521))
(CONNECT_DATA = (SID = test))
)

TCP-LOOPBACK.WORLD =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))
(CONNECT_DATA = (SID = ORC2))
)


Does anyone know how to sove this problem ?