signing in to SIP communication service failed

[GaryA]

Infrastructure:
Server: Windows 2003 Server running Live Communication
Server V 1.0.4949. Users created and Live communications
enabled for the users.

Client: Windows Messenger 5.0.

Error: "signing in to SIP communication service failed
because the sign-in name, username, or password is
incorrect, or the authentication service is not
compatible with this version of the program. If you have
signed in correctly and the problem persists, contact
your network administrator."

This error appears on clients from one of our sites, but
not from clients in the same site as the server. However
the clients on the remote site can ping the server, and
the server can ping the clients.

I am sure that the username and passwords are correct.

Has anyone got any ideas on this?

Regards,
GaryA.

 

[GaryA]

Hello All,

Just to let you know that I figured out the problem.
I set the Authentication method of the LCS server to NTLM
instead of "NTLM and Kerberos", and restarted the LCS
server. This allowed the users to login using Messenger
5, and not get the error.

Cheers,
GaryA.