If you are using Outlook 2007 with an SBS 2008 server you may notice the above error message when you try to enable Out of Office.
The Out of Office feature will work correctly in Outlook Web Access and in older versions of Outlook, it will only be broken in Outlook 2007.
Although not entirely sure we think the issue may occur if Microsoft Framework 3.5 SP1 has been installed on the Small Business Server. The issue is caused by a problem with the Framework package and is described in KB article 958934
To resolve this issue you have to obtain the hotfix from the article 952883