12Jan/100
OCS 2007 R2 Clients cannot connect to Lync Server due to authentication Service incompatibility
After migrating to Lync 2010 server some of my client users where not able to log in using OCS 2007 R2 clients due an incompatibility in the Authentication Service version.
I have checked the OCS 2007 R2 client logs, by browsing to %userprofile%\tracing\Communicator-uccapi-0.uccapilog and noticed the following error
010/08/2010|11:51:55.781 E0C:14A8 INFO :: SIP/2.0 401 Unauthorized

