You want to print the gridlines in a view, but they are not visible when you print your project .
Make sure the gridline color is dark enough to print clearly. Light gray, light blue, yellow, or white lines may not print clearly on black-and-white or color printers.
You can set gridline options for a task report or a resource report on the Details tab of the report's dialog box. On the Report menu, click Reports, select the report, and then click Edit.