By design the PanelBar control contains an internal ScrollViewer that wraps all items. Thus, even if you edit the default template of the items and add a ScrollViewer to each item, the individual ScrollViewers of the items will never show their ScrollBars since the ScrollViewer in their parent will always give them enough space to render. The motivation behind this is that the PanelBar is a hierarchical control.
From what you described, I suspect that the OutlookBar control
might be a better fit for your scenario since it is not hierarchical and would easily allow you to put ScrollViewers in the individual items. Let me know what you think.
the Telerik team
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