Is your sign on screen missing text? This issue occurs if video drivers overwrite the data in the font cache that is stored in memory. To resolve this issue simply download and run the following utility: http://www.dyknow.com/download/dev/fontcachefix.exe
You may find DyKnow freezes when signing on, joining a session, or opening a notebook. Additionally, DyKnow may be unable to render text or will render it in an unexpected way.