Most of the mathematical symbols come from the tciuni (for TCI Unicode) font that is installed with Scientific Notebook. You need to ensure that the tciuni font is correctly installed and is recognized by your system.
NOTE: Make sure that the Greek letters appear correctlygreeks before you attempt to fix any problems with the mathematical symbols. If the Greek letters appear correctly, your system is displaying Unicode fonts.
The instructions are different for Windows 95 and Windows NT. Be sure to click the operating system you have: