Four Update Rollups for versions of Exchange Server to the Download Center and via Microsoft Update :
Update Rollup 2 for Exchange Server 2010 SP1
This update contains a number of customer reported and internally found issues since the release of RU1. In particular we would like to specifically call out the following fixes which are included in this release:
Update Rollup 3 for Exchange Server 2010 Service Pack 1 is currently scheduled to release in February.
Update Rollup 2 for Exchange Server 2007 SP3
Update Rollup 3 for Exchange Server 2007 Service Pack 3 is currently scheduled to release in February.
Update Rollup 5 for Exchange Server 2010 RTM
This update contains an internally found issue which can impact upgrades from RTM RU4 to Service Pack 1. We have opted to release an out-of-band update rollup for Exchange 2010 RTM proactively to ensure customers have as smooth an upgrade experience as possible.
Currently, we have no plans to release future update rollups for Exchange Server 2010 RTM. We strongly recommend customers upgrade to Service Pack 1 with the latest Update Rollup after installing this update.
Update Rollup 5 for Exchange Server 2007 SP2
This security update was released earlier this morning via the Microsoft Security Response Center. Details of this bulletin and it's fix can be found below:
Currently, we have no plans to release future update rollups for Exchange Server 2007 SP2. Instead, we strongly recommend customers upgrade to Service Pack 3 with the latest Update Rollup.
Have a great Holiday Season :)
Kindest regards,
João Ribeiro