Some users have been experiencing error messages when using Print Preview in Outlook 2007 after installing the April Public Update . Print continues to work correctly despite the error message. We released an update as a Microsoft Hotfix that addresses the Print Preview error message and is referenced as KB article KB2512788 . If you are experiencing this issue, download and install the hotfix here . This update will also be part of a future Public Update distributed by Microsoft Update.
Read more at source: http://blogs.office.com/b/microsoft-outlook/archive/2011/04/29/fix-for-issue-with-april-public-update-for-outlook-2007.aspx