My corporate IT department has mandated a change to Microsoft's Lync for instant messaging, among other purposes. I installed it and launched; it automatically found the server it needed, since my corporate address book was available and I could IM folks in it. I then added a contact outside my company and it found the person even before I finished typing the name; she is listed with "presence unknown" in my contacts list (IM service is MSN). When I attempting to send an IM, however, I think it tried to tell me it failed. (I am not sure because it did not say it failed(!); it just mentioned that "When contacting your support team, reference error ID 504 (source ID 239)." I thought, "Well that was nice of it to be so proactive; if and when I have a need for support, I have a number to provide--yay!")
A web search for the error code did not shed any light for me; the Lync overview page indicates outside IM contacts may be used, so any suggestions on how to make this IM connection work?