Office Communicator 2007 R2 backwards compatible?

A while back I installed Office Communicator 2007 R2 in an R1 environment and interestingly as other sites suggest you can login and use an R1 OCS server with the R2 client.

A number of things transpired and therefore I would strongly recommend that you avoid this in production.

  • As you might expect R2 options are not functional
  • Office Communicator Phone edition was no longer able to login
  • Enterprise Messenger for BlackBerry was also unable to login
  • There may be more issues that I have not been able to re-produce

Logic suggests that after logging into an OCS R1 server with the R2 client, a number of database updates are automatically applied. This can be reversed by deleting and re-creating the OCS profile. Curious people should avoid, avoid and avoid! [:)]