When previewing stubbed messages in Outlook 2007, You receive this message "This item contains active content that cannot be displayed in the Reading Pane..."
You start Outlook 2007 in Cached Exchange Mode and with the reading pane active. If an e-mail message that contains a custom form that has code is selected, and the MessageClass is changed, the custom form and the code are displayed unexpectedly in the reading pane. For example, this issue occurs if the MessageClass is changed to IPM.Note.ReadEvent. Additionally, CPU usage may be greater than expected.
Upgrade to Archive Manager 3.7
Request and download the hotfix for http://support.microsoft.com/kb/939596
Clear the forms cache with http://support.microsoft.com/kb/940556/
Do the following to turn the reading pane back on for newly stripped messages, or re-stripped messages.
Set the AM configuration setting "Disable Preview Pane" to false using the AM configuration editor
Restart the ESM
For any message that is currently stripped, open the message in Outlook to reconstruct it. When the ESM re-strips the message it will add the property to the message that allows Outlook to display it in the reading pane.