cant connect to sql server, error

hi if someone could help, i appreciate: i have windows 2003 server and sql server 2000, i have a few machines connected via odbc and seems to work fine, my problem is when i try to make a new connection via odbc, appears: sql server odbc error: ConnectionOpen and server does not exist or access denied, i try few things, make a ping to the server and i got response, check the users and passwords, the mdac, check that the port 1433 is established in the client network utility, etc, now when i do a telnet to the server the port 1433, appears and error: couldnt connect,i believe this is why i cant make a odbc connection, but i cant figure it out how to make the port listens my petitions., now if itsa supossed to be closed, why the others machines cant connect just fine?

Do you already review the firewall for sql server ports?

http://support.microsoft.com/kb/287932/en