Currently I am trying to connect to sql server 2000 via database link but the following error prompts.

SQL> select * from products@northwind;
select * from products@northwind
ERROR at line 1:
ORA-28545: error diagnosed by Net8 when connecting to an agent
NCRO: Failed to make RSLV connection
ORA-02063: preceding 2 lines from NORTHWIND

Could anybody help me on this.