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Query: “ but instead creates input boxes and blank buttons below the Grid.”
From your query, we understand that you are facing issue while opening a excel filter dialog for certain column.The reported issue may occur when there is no record in ejGrid. Or Initially rendering the Grid with empty data and later updated the dataSource. By default Grid column will assign its type based on first record. But when we bind empty dataSource to Grid, values will be null and column type will not be assigned. Hence the reported issue occur.
To overcome the reported issue, we suggest you to specify Type property of the column to perform the filtering operation.
Refer to the code example:-
<ej:Grid ID="Grid1" runat="server" AllowPaging="true">
<ej:Column Field="OrderID" />
<ej:Column Field="CustomerID" Type="string" />
<ej:Column Field="EmployeeID" Type="number" />
. . .
Refer our UG and KB document fr your reference
Please get back to us if you need any further assistance.