Getting this error when installing OCS R2? The Log shows this also:
Failure [0xC3EC79E6] Service failed to start as requested.
This is due to not having the correct Services installed prior to OCS R2 rollout. It's a bug of the actual Product installation as it doesn't state it is needed, and you will find when you finally get to start the Services you are presented with this confusing and frustrating error.
Install Windows Powershell if not already present on your Windows 2008 Server. Run the following commands:
ServerManagerCmd -i MSMQ-Services
ServerManagerCmd -i MSMQ-Server
You will find the first one should install the second as a pre-requisite.
Re-run the Start Services wizard in the OCS 2007 R2 Deployment Wizard, and voila! you now have a happy service state.
Here's a visual view of what you get and how to remedy:
MVP - Exchange Server