To help minimize the impact of migration on user productivity, include the following client-related considerations during the migration planning phases.

• In Lync Server 2010, most of the Group Policy settings used in previous Office Communications Server releases are now controlled by in-band provisioning client policies that are server-based. You can manage these settings by using the Lync Server Control Panel, the Windows PowerShell command-line interface, or both. For details about how Group Policy settings in your existing deployment map to Lync Server 2010 settings, see Migrating User Settings to Lync Server 2010.
  
  
• Determine how Lync Server 2010 clients will interact with previous client versions. For details, see Client Interoperability.
  
  
• If you are deploying conferencing, you’ll need to understand how meetings have changed in Lync Server 2010 and determine how migration will affect new and existing meetings. For details, see Migration Considerations for Meetings.
  
  
• For manager-delegate support, both managers and delegates must be migrated to Lync 2010 at the same time.
  
  
• Decide how users who do not have Lync 2010 installed will participate in Lync Server 2010 meetings and configure the meeting join page accordingly. For example, in addition to Lync Web App, you can allow users to join meetings by using Microsoft Lync 2010 Attendee or a previous version of Communicator. For details, see Configure the Meeting Join Page.
  
  
• Verify that the Enhanced Presence bit is set to True on Office Communications Server before you run the Move-CsLegacyUser cmdlet to migrate users. If this bit is not set to True, an error occurs during the user migration. When you set Enhanced Presence to True and rerun the cmdlet, users lose their blocked Contacts lists.
  
  

  Tip:
  You can verify the Enhanced Presence bit by using the Snooper tool that is available in the Office Communications Server 2007 Resource Kit. Run Snooper on a computer running Office Communications Server 2007. Click Reports, click Conferencing and Presence Reports, type the user information, and then click Generate Report. In the results, verify that RichMode is set to True.

• Users who use Office Communicator 2007 or Office Communicator 2007 R2 (rich presence clients) need to log on to Office Communications Server at least once before you migrate users. If a user has not logged on to Office Communications Server before you migrate users, the user loses the blocked Contacts list.
  
  

Phases 2 and 8 of the migration process include specific steps for migrating clients. These steps are summarized later in this topic. For details, see the steps for these phases in the migration process.

In Phase 2: Prepare for Migration, use client version rules on your existing server to allow only clients with the most current updates to sign in, and to block Lync Server 2010 clients from signing in.

In Phase 8: Complete Post-Migration Tasks (Office Communications Server 2007 Migration), after users have been migrated to Lync Server 2010, do the following:

1. Use client version rules on the server running Lync Server 2010 to allow only clients with the most current updates installed to sign in.
   
   
2. If necessary, configure the Group Policy settings that are required for client bootstrapping. For details, see Key Client Policies and Settings. Configuration of these settings is only necessary if you want to change existing client bootstrapping policies or if you want to set new client bootstrapping policies. If you do not plan to configure client bootstrapping policies, or you want legacy client bootstrapping policies to remain in effect, no action is necessary.
   
   
3. Configure other user and client policies for specific users or groups of users by using Microsoft Lync Server 2010 Control Panel, Windows PowerShell, or both.
   
   
4. Deploy the latest version of Lync Server 2010 along with the latest cumulative updates.
   
   
5. (Optional) If your organization requires Lync 2010 enhanced presence privacy mode, after migration is complete, define a Client Version Policy Rule to prevent earlier client versions from signing in. Then, enable enhanced presence privacy mode. For details, see Configuring Enhanced Presence Privacy Mode in the Deployment documentation.
   
   

   Important:

   Do not enable Lync 2010 enhanced presence privacy mode until every user on a given server pool has the most current client versions installed. Lync 2010 privacy settings are not honored by earlier client versions. If earlier clients are allowed to sign in, a Lync 2010 user’s availability, contact information, or photo could be viewed by someone who has not been authorized to do so. Additionally, a Lync 2010 user’s privacy management options are reset if that user subsequently logs on with an earlier version of the client.

6. (Optional) If you use remote call control, create a group policy to set the Enable integration with your phone system option in the Phone integration section in Lync 2010.