Update Rollup 3 for Exchange Server 2010 SP2 Installation Procedures
As with any roll ups it's required to disable the ForeFront Controller Service prior to running the roll up by running fscutility /disable. What this does removes the ForeFront Controller Service dependency from the Exchange Transport service. I've personally never ran this on previous rollups knowing it was required and never had a problem. However with this rollup I got bit. After spending approximately 1hr 20 mins for the rollup to almost complete it was stuck at starting services because the transport service could not start because of the ForeFront Controller dependancy so it rolled back the entire install.
When you run the fscutility /disable (from the forefront directory in using cmd) it wll say that it was sucessfully in removing the dependency. However, you may get a warning that it failed because the transport and ForeFront Controller Service was running. In this case stop the services and re-run the command.
Once the rollup is completed you need to run fscutility /enable. Again you may get an error that it failed because the MS transport and ForeFront Controller Service is running. In this case stop the services again and re-run the command. I would also reboot when all is complete.
Since rollups take anywhere from 1hr to 1.5hrs, you want to make sure you also remove the patching servers out of any load blancing pool whether hardware based or NLB.
As with any rollups and service packs you also want to start with your EDGE, CAS\HT first then your Mailbox servers.
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