Hello Daniel,

I have been looking into your questions and in order to preserve the resizing functionality when the XamOutlookBar is minimized I can suggest you handle the NavigationPaneMinimized and NavigationPaneExpanded events as follows:

        private void XamOutlookBar_NavigationPaneMinimized(object sender, EventArgs e)

        {

            col1.Width = new GridLength(XamOutlookBar.ActualWidth, GridUnitType.Auto);

        }

        private void XamOutlookBar_NavigationPaneExpanded(object sender, EventArgs e)

        {

            col1.Width = new GridLength(XamOutlookBar.ActualWidth, GridUnitType.Auto);

        }

In my snippet col1 is the name of the Grid’s column where the XamOutlookBar is contained. This will ensure that every time the XamOutlookBar is minimized or expanded the column’s width will not be set to a fixed size.

For further reference, please have a look at the attached sample.

If you need any additional assistance on this matter, please do not hesitate to let me know.