Error: service '?' unknown in Load Balance

Hi,

I'm configuring SAP load balancing.

I've configured the group in SMLG, and now I'm trying to add the logon properties in SAP GUI.

My current landscape is:

Node 1 and node 2 configured in cluster environment.

ASCS is started on node 1.

Now, in saplogon properties, I have:

System ID: <SID>

Message server: hostname of node 1

Group/Server: Error: service '?' unknown

I've added entry in services file:

sapms<SID> 36xx/tcp

And disable firewall.

Still same problem.

(I can't telnet to that port, though).

Thanks for help.

Regards,