The font used in the drawing is not present on the PC on which SilicaCAD® is installed. Font installation is required. 
or 
Make sure that a font search path is present among those displayed in the menu Tools -> Options -> Paths/File -> Support paths -> Fonts. If it is not, add the character “;” after the queued existing routes and then the font path. 
or 
Verify that the font replacement is not active. Open with a text editor (e.g. “Notepad” Windows) the file “icad.fmp” that is situated in Start menu of Windows -> All Programs -> SilicaCAD 2XXX Pro ENG -> Utility -> SilicaCAD 20XX Professional Center  -> Settings  -> User Support Folder. 
Example: 
The font not properly displayed is “romans”. After verifying the installation of the font on your system and therefore the presence of the full path among those displayed in the fonts location (Tools -> Options -> Paths/File -> Support paths -> Fonts), open the file “icad.fmp” and remove the row with the following content: “romans; ic-romans. shx. ” This will avoid the replacement of fonts.