Exchange CXP team has released Update Rollup 4 for Exchange Server 2010 RTM (KB 982639) to the download center.
KB 982639 lists all the fixes included in this rollup. Here are some of the product improvements and critical bug fixes we'd like to call out starting with 5 improvements we made to prevent crashes in very unique scenarios.
We corrected a few replication issues some of you encountered.
One unique thing added was an ability for an administrator to adjust filtering of XML attachments so an OWA user can save them. Some customers were facing a compliance versus level of security tradeoff. See more about configuring this option in KB 983200, which discusses adding administrator control over attachment stripping. We also included at least eight other fixes that some of you requested in this release which we already had worked on for a service pack but are able to deliver to you sooner.
KB 982639 has more details about this release and a complete list of all fixes included in this worthwhile rollup.
For those of you running Forefront, be sure you perform these important steps from the command line in the Forefront directory before and after this rollup's installation process. Without these steps, Exchange services for Information Store and Transport will not start back up. You will need to disable ForeFront via "fscutility /disable" before installing the patch and then re-enable after the patch by running "fscutility /enable" to start it up again post installation.
Please go to our Update forum: http://social.technet.microsoft.com/Forums/en/exchangesoftwareupdate
If you use a GPO to define the Windows PowerShell execution policy, you probably had problems installing previous RUs. We have addressed this problem in this Update.