I created some custom Outlook forms to automate some of my sales response tasks and then Outlook started to complain about the item contains active content that cannot be displayed in the preview pane. Today I finally found an answer in the M$ knowlegebase article, Q331788. It said I needed to apply a hotfix and manually edit the registry. I checked the file versions and my files are up to date. As much as I dislike editing the registry this fix cleaned up the problem.