When a PDF is created, the author should "embed" the fonts. If they didn't, and your computer doesn't have that exact font installed, the system defaults to showing the technical name of the missing font. 2. Corrupt PDF Metadata
If you receive an error saying a CIDFont "cannot be created or found," it usually means the PDF was exported poorly and the font data was not correctly embedded. Impossible fonts to be found / Fontes impossíveis de achar Cidfont-f1 F2 F3 F4 F5 F6
The genius of the Cidfont system lies in its fluidity. A single document might begin with an F3 paragraph, shift to F4 for a key definition, quote a source in F2 footnotes, and close with an F6 signature line. A digital interface could animate through the spectrum: subtle F1 loading text transitions to F2 instructions, then F3 content, with interactive buttons set in F4. A poem might move from F5’s expressive title through F3 stanzas, ending in F6’s final couplet. Because all six variants share consistent underlying metrics (x-height, baseline, kerning pairs), they can be mixed without jarring the eye—a true typographic instrument, not a collection of unrelated styles. When a PDF is created, the author should "embed" the fonts
After conducting a thorough search, I found a paper related to the topic: Corrupt PDF Metadata If you receive an error