As it was previously noted, by default, RadGridView handles the drag and drop operation by its RadGridViewDragDropService. The mentioned events, DragEnter and DragOver, are relevant for the OLE drag-and-drop functionality and they are not supposed to be fired if you use the RadGridViewDragDropService.
In case you don't want to use the available service in RadGridView, an alternative approach is to implement the desired drag and drop behavior with the standard approach supported by all MS standard WinForms control. A sample tutorial is demonstrated in the following MSDN article: https://docs.microsoft.com/en-us/dotnet/desktop/winforms/advanced/walkthrough-performing-a-drag-and-drop-operation-in-windows-forms?view=netframeworkdesktop-4.8
The following forum post also demonstrates a sample approach of using the OLE drag drop and achieving dragging a file from Outlook and dropping onto the grid: https://www.telerik.com/forums/drag-and-drop-into-radgrid
However, I believe that the RadGridViewDragDropService would also fit your scenario even though it provides other public events
Feel free to use this approach which suits your requirements best.
However, if you are still experiencing any further difficulties, it would be greatly appreciated if you can provide more details about the exact goal that you are trying to achieve. Thus, we would be able to get better understanding of the precise case and think about a suitable solution.
Dess | Tech Support Engineer, Sr.
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