Migrating from LCS 2005 SP1 to OCS 2007 - which client can you use when?

During migration from LCS 2005 SP1 to OCS 2007 you will have to understand which clients can be used under which conditions during the migration. When I talk about clients I'm referring to Office Communicator 2005 (OC 2005), Office Communicator 2007 (OC 2007), Office Communicator Mobile 2005 (CoMo 2005), Office Communicator Mobile 2007 (CoMo 2007), Communicator Web Access 2005 (CWA 2005) and Communicator Web Access 2007 (CWA 2007).

In the following table I have tried to illustrate when a given client can connect to a given server and under which conditions. The sequence of rows is meant to simulate the normal migration sequence from LCS 2005 SP1 to OCS 2007.

Row Client connects with User homed on Enabled for Enhanced Presence Enhanced Presence Mode set Connection works?
1 OC 2005 LCS 2005 SP1 N/A N/A Yes
2 OC 2007 LCS 2005 SP1 N/A N/A No
3 OC 2005 OCS 2007 No No Yes
4 OC 2007 OCS 2007 No No No
5 OC 2005 OCS 2007 Yes No Yes
6 OC 2007 OCS 2007 Yes Yes (sets it on first successful connection) Yes
7 OC 2005 OCS 2007 Yes Yes No

In the following I will use OC 2007 to cover all the new clients OC 2007/CWA 2007/CoMo 2007 and OC 2005 to cover the old clients OC 2005/CWA 2005 and CoMo 2005.

The first 2 rows shows that OC 2005 can connect to LCS 2005 SP1, but OC 2007 can not. Row 3 shows that OC 2005 can connect to OCS 2007 as long as the user has not been enabled for Enhanced Presence and Enhanced Presence Mode has not been set. Enhanced Presence is the new presence architecture implemented in OCS 2007. Row 4 shows that OC 2007 can not connect to OCS 2007, if the user has not been enabled for Enhanced Presence. Row 5 shows that OC 2005 can connect to OCS 2007, even if the user has been enabled for Enhanced Presence, but only as long as Enhanced Presence Mode has not been set.

Enhanced Presence Mode is set the first time OC 2007, CWA 2007 or CoMo 2007 successfully connects to the server. Row 6 shows that OC 2007 can connect and that it sets Enhanced Presence Mode on first successful connection. Row 7 shows that after the user has been Enabled for Enhanced Presence and Enhanced Presence Mode is set only the new clients can connect.

When a user is moved from LCS 2005 SP1 to OCS 2007 he/she is not automatically enabled for Enhanced Presence. When a user is created on OCS 2007 he/she is automatically enabled for Enhanced Presence, but Enhanced Presence Mode is not set. If a user has been enabled for Enhanced Presence he/she can not be disabled for Enhanced Presence.

Enabling a user for Enhanced Presence can be done using the Active Directory Users and Computers MMC snap-in (User Properties -> Communications -> Configure -> Enable enhanced presence), through the OCS 2007 Administration MMC snap-in (Users -> Properties -> Configure -> Enable enhanced presence) or through WMI by setting the EnabledForEnhancedPresence user property on the relevant instance of MSFT_SIPESUserSetting (see the LCSEnabledConfigureUsers.wsf script in the OCS 2007 Resource Kit Tools for a way to do it).

To check if a user has Enhanced Presence Mode set use the OCS 2007 Resource Kit tool dbanalyze. Run a report on the user like this dbanalyze /report:user /user:<SIP URI of the user> and check the output for the RichMode row. If RichMode is True then the user has Enhanced Presence Mode set.