Font linking helps resolve the situation when fonts on a deployment machine do not have the glyphs that are used in a development environment. When you find such a glyph mismatch, there is a possibility that the PDF output on development and deployment machines may be different.

In order to resolve this issue, the PDF export filter or the PDF rendering extension looks for the missing glyphs in the installed fonts as follows:

• Checks the system font link settings for each font that is used in the report. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\FontLink\SystemLink registry key stores the information on font links.
• If font links are not set or the needed glyphs are not found, searches for the glyphs in the fonts declared in the FontFallback Property.
• Uses glyphs from the font links collection to replace fonts that do not have their own declared linked fonts.
• If necessary glyphs are not found by font links or in the fonts declared in the FontFallback property, glyphs from Microsoft Sans Serif font are taken as the predefined font.