First thing, what is the color? If it is using the [Paper] swatch it isn't really a color and won't print.
Next, check Preview mode to see if the color is still visible, if not, either the object or the layer is set to non-printing.
Finally, check the printer driver for a setting like Print Background Color. It used to be pretty common to not print the backgrounds from web pages.
Oh, and I forgot...
Is the color there when you export to PDF? Does it print correctly from the PDF? There are some printers that just don't get along with ID.