Random Ramblings of a Microsoft Guy

Microsoft Cloud, Automation, Manageability, Virtualization, and whatever else that comes to mind..

OCS 2007 to OCS 2007 R2 Migration

I recently had the pleasure of working on an environment that was working on a migration from OCS 2007 Std to OCS 2007 R2 Ent.  The 2 environments were installed in parallel and were not separated by any network firewalls or any other communication filtering.

The issue that was occurring was that when any user was moved from the old pool to any of the pool’s on the new R2 environment, that user would not be able to communicate with any user still in the old pool.  Needless to say, this was a major problem for the migration.  After some research, we were able to nail it down to an “old server” to “new server” communication problem.  The communicator client worked no matter which server you pointed to or which pool your account was in.  This further enforced server-to-server communication to us.  Here is some error information that we were getting:



With some research and consultation,

 we found that there were some patches that could have an impact, so we gave them a try.  After installing hotfixes KB957465 KB956389 on the old server and the communicator client, we rebooted the old server and the server-to-server communication began working immediately.  These patches and the reboot resolved the issue for us.  Once that was working, we noticed that no more than 2 people could join a session on the new pool’s.  A few minutes of research later, and we found that KB974009 fixed the issue. 


So if you are having communication problems while doing an OCS migration, those hotfixes/procedures may help you.