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I'm using tabs in my app. I'm aware of at least one customer-reported exception, that I can't reproduce, in which four document windows were open and the DockSite.TileDocumentsVertically command was issued:
"InvalidOperationException: This operation is invalid since the DockingWindow has not yet been registered with a DockSite."
Relevant stack trace:
ActiproSoftware.Windows.Controls.Docking.DockingWindow.Activate(Boolean focus):57
ActiproSoftware.Windows.Controls.Docking.TabbedMdiHost.TileVertically(Int32 maxRowCount):364
ActiproSoftware.Windows.Controls.Docking.TabbedMdiHost.TileVertically():9
ActiproSoftware.Windows.Controls.Docking.DockSite.TileDocumentsVertically():40
Is this a confirmed Actipro bug which has been fixed in a later release? I can't currently upgrade due to project scheduling/risk constraints.