Program-driven tab switching in Outlook FormRegion

Question

I'm building an Outlook FormRegion with a tabControl, with about 75 tabs (Outlook 2007, VSTO 2008, and yes I'll probably "hide" a bunch of them in production). As a result of a button click on one tab I need to switch to another tab. This didn't seem to be such an obstacle until every solution I tried resulted in a "... does not exist in the current context." That context being the button_Click. Regards,