I have a oracle server running on a linux box. And I just loaded the client on a Sun Solaris box.

When I tried to run sqlplus from my Sun's box, I got the following error.
ORA-12545: Connect failed because target host or object does not exist

Here is my tnsnames.ora
tstdams =
(ADDRESS = (PROTOCOL = TCP)(HOST = oddjob)(PORT = 1521))
(SID = tstdams)

Any idea?

oddjob is defined in /etc/hosts file ( I tested with tnsping)
ORACLE_HOME and ORACLE_SID are defined.