Tab.Index Property (Outlook Forms Script)
expression A variable that represents a Tab object.
The Index property specifies the order in which tabs appear. Changing the value of Index visually changes the order of tabs on a TabStrip. The index value for the first tab is zero, the index value of the second tab is one, and so on.
In a MultiPage, Index refers to a Page as well as the page's Tab. In a TabStrip, Index refers to the tab only.