The RadSpreadsheet control has a built-in navigation that changes the active cell when you press the arrow keys or the Return/Enter key. When you enter the cell's edit mode, the left and right arrow keys navigation will kick in only if you are the end or the beginning of the cell's content. You can test this behavior in our demo
However, without your scenario I can't be sure why the navigation doesn't work. Can you give me more details about it? How you enter edit mode? What content you have in the cells? What is the set up of the spreadsheet control? Also, it would be helpful if you can share some runnable code that I can check locally.
In addition to my reply, I noticed that you post this question in 3 different forums. I am going to delete them because they are duplicate of this one. Moreover, the sections where are posted are not related to the RadSpreadsheet control.
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