If one of the available DPI setting doesn’t yield satisfactory results or if you just want to experiment a little, you can click, Set Custom Text Size (DPI)
When you do, you will see the Custom DPI setting dialog box. Keep in mind that if you use a DPI setting higher than 96, the text and other graphical items in programs that are not designed to work with the DPI scaling engine might appear blurry. To compensate for those types of programs, Windows 7 incorporates a backward compatible DPI scaling feature that will kick in when you run those programs.
Make sure that the Windows XP style DPI scaling check box is NOT selected when your DPI scaling is set up for Prokon software.