Removing from the inside
WARNING: This page is about a different car, the 2011 BMW 750xi, 2011 BMW 750Lxi, 2010 BMW 750xi, and 2010 BMW 750Lxi. However, it is still accessible from the selected car via links, so may be relevant.
Guide knife carefully between body and window glass.
Run blade of knife parallel to glass.
Take care not to damage paintwork.
Cut through adhesive bead all the way around.
Pull window glass outwards to remove.