Now after a few weeks of testing and re-engineering Microsoft has re-released Update Rollup 3 as Version 2.
On March 14th we posted an announcement to the EHLO blog about removing Update Rollup 3 for Exchange Server 2010 SP1 due to an issue related to Blackberry devices.
The Exchange Servicing team has fixed the reported issue with E2010 SP1 RU3 and is making available a new version of RU3 for our customers, version 14.01.289.007, (KB2529939). We strongly advise all customers install this newly released version of Microsoft Exchange Server 2010 SP1 Update Rollup 3 and to discard any prior version of RU3 (KB2492690) which you may have.
For customers that had already deployed the original Update Rollup 3 and have not yet uninstalled it this new Version 2 of the update can be installed straight over the top. For the full deployment advice see the Microsoft Exchange team blog.