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Drawing objects (pictures, shapes, comments, etc.) support custom RGB colors that may or may not be present in the palette. If you modify the color of an AutoShape (right-click the shape and select "Format AutoShape"), for example, and select a non-palette custom color, the change will not affect the workbook palette or other elements in the workbook to which the replaced color was assigned. To set custom values for shape fill and line colors, use Shape.SetCustomFillColor and Shape.SetCustomLineColor.
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For more information on creating a custom palette for XLS files, refer to Excel's Color Palette Explained. |
The color palette in xml (.xlsx, .xlsm, etc) files
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