RadGrid provides drag-n-drop functionality for its rows, but not for cells:
I can see that you have the AllowRowsDragDrop property disabled, which should mean that the item dragging is disabled. You can also check your Columns definition for GridRowIndicatorColumn.
I've created a sample RadGrid web site using your exact grid definition code snippet. Could you run the attached application and modify it to demonstrate the mentioned dragging? Or you can send us sample screenshots or video. This will enable us to replicate the described behavior locally and provide more precise and accurate suggestions.
You can run the Web site by following these steps:
1. Open Visual Studio
2. File menu
3. Open option
4. Select Web site and target the web site folder.
5. Include a Bin folder with the Telerik dll assemblies.
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