How can my Outlook VSTO Add-in modify the read email form?

Question

Depending on the text in an email being viewed, I would like my VSTO Outlook Add-in to use a modified form to display the email.

I am able to create custom panes, but they do not show up where I want them. I can also create Outlook form regions that are "Adjoining" and show up at the bottom. But I have not been able to modify either of the two default forms that outlook uses to display email messages - the inspector read form, and the reading pane form used in the main outlook window. (I apologize if I'm using the wrong terms.)

This is where I'd like to insert some text labels and buttons and such right above the email message:

Is this possible? A page at MSDN says I should be able to customize any standard form.

Thank for for your help.

Answer 1

Outlook (nor VSTO) doesn't provide anything for placing custom forms at the top of inspectors. Outlook Form Regions doesn't provide such layouts. You can use Windows API functions for subclassing Outlook windows and placing custom forms where you need them. See the Adjacent Windows In Outlook article and Creating Adjacent Windows In Outlook sample project for more information.

You may also consider using Advanced Outlook view and form regions. They allow to place the form at the top position of the inspector window.