What? You want to disable IM in Lync? Why on Earth would you want to do that!
It turns out there are a number of reasons that some organizations might want to, including:
Whatever the reason, there’s a simple way to disable IM via a registry setting on the Lync Client. It’s actually a hold over from the Office Communicator client, and the setting is described in BLOG post here as well in a KB article (KB954648).
All that’s required on the client machine is:
What happens? The user can’t participate in IM conversation, using the Lync client, that’s what happens! One easy way to see the impact is by looking at contact cards before / after the change – the IM “bubbled” is greyed out. Two pictures of contact cards make the point best:
Doesn't work for Lync 2013. Is there a new regkey location perhaps that would?
Thanks Cowbelly. Although, the solution you gave only works for OCS 2007. In order to get this working for Lync 2013, I applied it in this location HKEY_Local_Machine\Software\Policies\Microsoft\office\15.0\Lync.This blog, has more information about this http://corporateitsystems.blogspot.com/2014/03/disable-chat-in-lync.html