I know it's been quite a while, but I'm having a similar issue except mine occurs on any windows 7 machine (works fine on XP, Vista, Server 2008, etc and was working on Win 7 for a while), not sure of the cause...did you ever come up with a solution?

Thanks for the tips...it turned out that the grouping passes the grouped data as "Name" rather than it's actual path name so all I had to do was change my binding from "Vendor" to "Name" in the text binding...guess it's just one of those oddities of programming...lol. Thank you!

Hey guys, I read a couple of the articles on here as well as the MSDN Sample for this task however I seem to be stuck; was hoping you guys could help me. The following is my code, and although the items appear in the list perfectly, the ExpanderHeader appears with no text despite my text binding and I haven't the foggiest idea what I'm doing wrong. Any help would be greatly appreciated! <Setter Property="Margin" Value="0,0,0,5"/> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="{x:Type GroupItem}"> <Expander IsExpanded="False" BorderBrush="SlateGray" BorderThickness="0,0,0,1"> <Expander.Background> <RadialGradientBrush> <RadialGradientBrush.RelativeTransform> <TransformGroup> <ScaleTransform ScaleX="1.702" ScaleY="2.243"/> <SkewTransform AngleX="0" AngleY="0"/> <RotateTransform Angle="0"/> <TranslateTransform X="-0.368" Y="-0.152"/> </TransformGroup> </RadialGradientBrush.RelativeTransform> <GradientStop Color=</x-turndown>