I have looked over other questions related to style definitions, and looked through the Mathematica 8 [documentation][1], but I do not know why I am having so much difficulty setting the default font in my free .CDF files. I have tried changing the cell appearance to the desired font style many times for Default.nb as shown in the attached image, but the changes never take effect, and whenever I go back to "Edit Stylesheet" for Default.nb, all my changes are gone! The style changes don't show up after I've changed the style's appearance, and don't show up when I hit ENTER to enter in new input. As shown in the second input cell in the image below, Mathematica continues to default to Courier New. The first input cell has the desired font shown for comparison, where I set the font that specific cell only. This is driving me nuts. All I am trying to do is set the default input/output font to Consolas 11. ![enter image description here][2] [1]: http://reference.wolfram.com/mathematica/ref/menuitem/EditStylesheet.html [2]: https://i.sstatic.net/yelXM.png