Edit: Update Rollup 18 is now available for Exchange 2010 SP3 see the post Exchange 2010 SP3 Update Rollup 18 installation tips.
On August 28th Microsoft released the Exchange 2010 SP3 Update Rollup 7. The Update Rollup 7 for Exchange Server 2010 SP3 contains the fixes for the security issue that is described in KB2961522.
Update Rollup 7 for Exchange Server 2010 SP3 resolves the issues that are described in the following Microsoft Knowledge Base (KB) articles:
2983261 “HTTP 400 – Bad Request” error when you open a shared mailbox in Outlook Web App in an Exchange Server 2010 environment
2982873 Outlook Web App logon times out in an Exchange Server 2010 environment
2980300 Event 4999 is logged when the World Wide Web publishing service crashes after you install Exchange Server 2010 SP3
2979253 Email messages that contain invalid control characters cannot be retrieved by an EWS-based application
2978645 S/MIME option disappears when you use Outlook Web App in Internet Explorer 11 in an Exchange Server 2010 environment
2977410 Email attachments are not visible in Outlook or other MAPI clients in an Exchange Server 2010 environment
2976887 eDiscovery search fails if an on-premises Exchange Server 2010 mailbox has an Exchange Online archive mailbox
2976322 Assistant stops processing new requests when Events in Queue value exceeds 500 in Exchange Server 2010
2975988 S/MIME certificates with EKU Any Purpose (220.127.116.11.0) are not included in OAB in Exchange Server 2010
2966923 Domain controller is overloaded after you change Active Directory configurations in Exchange Server 2010
The update can be downloaded from here.
I’ve installed this on my test SBS 2011 server, it took just 11 minutes from start to finish, and my test SBS server isn’t very powerful. So I wouldn’t expect this to take much longer than this in production.
The update has been available for a month now, and I have not seen any issues with it so I suspect it is safe to deploy in your production environment.
While looking for others experience of installing the update rollup I’ve come across a few suggestions that might help speed the install up and a few best practice tips.
1. Reboot the server prior to installing the update rollup. If it has been up for a while a reboot will make sure it is in a know good state.
2. Run the update from an elevated command prompt.
3. In Internet Explorer, deselect “Check for Publisher’s certificate” and “Check for server certificate revocation”, from Internet Options, Advanced tab, Security options.
4. Disable antivirus software.
5. Have a full backup and a system state backup of the server.
6. Make sure the SBS console is closed if installing the update on SBS 2011.
7. Backup any OWA customisations you have in place.
While the update is installed it will automatically stop Exchange and IIS services, and restart them again once complete.
Once the update has finished, remember to undo the changes made in steps 3 and 4 above.