For smooth upgrade client experience going from OCS 2007 R1 to OCS 2007 R2 - update the Office Communicator R1 client to v2.0.6362.111 (December 2008 release - KB 957465)

There is an interesting gotcha that can affect users when you are in the middle of an OCS 2007 R1 migration to OCS 2007 R2. If you migrate users to R2 and they attempt to log into Communicator with a pre-December 2008 release of the client, there is a chance they will have the program crash. This is also true for the original RTM release of the Communicator Mobile client. Thankfully, there is also an update available that you or your users can install before migrating.

Download links

Communicator R1 update
Communicator Mobile update

I wrote previously about the other updates related to the December 2008 Communicator release here.

If you are unsure of what versions of the Office Communicator client your end users are using, you can pull up a database report inside the R1 or R2 administrator console and view this data. Thanks go out to Andrew Hitchcock for showing me and reminding me that this was possible in both OCS 2007 versions.

In the example below, there are a few users still running the OCS R1 RTM Communicator release (v2.0.6362.0), a few are running the update from April 30, 2008 (v2.0.6362.64), and the rest of running the OCS R2 RTM client (v3.5.6907.0).



Another tip for migrating: You should also do a Microsoft Update on all your R1 servers before migrating users over to R2, because they will then download the other server-specific inter-op updates so that the R1 and R2 servers will be able to co-exist properly.