Currently, Standard fonts are exported always with StandardEncoding. This does not allow export of some special characters which do not fit in the first 255 glyph definitions in the font. Most of these characters are the ones with an accent such as "Eacute" glyph (É) which is with position number 303 in Times Roman font. The list of all standard fonts may be found in this documentation section: https://docs.telerik.com/devtools/document-processing/libraries/radpdfprocessing/concepts/fonts#standard-fonts