Thanks for writing.
To draw vertical grid lines, you need to set your axes on the chart, not on the series. This is crucial since the grid does not know which series to get axes from if the axes are set on the series. Once the axes are set on the chart object, you just have to set the grid to render only vertical lines. For example:
CartesianChartGrid grid = new CartesianChartGrid();
You need to stop the palette from applying because otherwise it will overwrite your settings.
Please write again if you have more questions.
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