If you are using a special font, it is critical that you include the font when sending your artwork, you may select the font by finding it in your font directory and saving it to your desktop, then attach it with your artwork when sending. If you use the Style palette to modify your font, it must be converted to outlines, or saved as a rasterized flat layer image.
Most of your font files are located in the C:\WINDOWS\FONTS\ directory. To make things easier on all of us, send your Font File with your artwork submission.