We're seeing reports of problems with Outlook 2007 following the installation of the December 14 update for Outlook 2007 (KB 2412171). A number of users are reporting performance issues with Outlook 2007 after installing the update described in KB 2412171. If you are affected you may experience slow performance when changing folders. This slowness is more pronounced when the folders are in different message stores. Additionally, users with email accounts that use Secure Password Authentication (SPA) or users of Outlook Anywhere (RPC over HTTP) with NTLM authentication may receive errors when downloading email. Users who use the archive feature may notice that archive does not work or has disappeared.
Until Microsoft identifies the cause and a hotfix is released, if you have issues with the update you'll need to uninstall this update and configure Windows Updates to 'hide' the update so its not downloaded again.
To hide the update, first uninstall it then go to the Start menu and click the link for Windows Update. Let it search for updates it thinks you need then review the list. Right click on the updates you don't want installed and choose the option to hide. If the update is enabled (checked) for installation, hiding it will remove it from the installation list.
Published December 16, 2010. Last updated on June 17, 2011.