If you only have the broken PDF file, you can try rebuilding it using an open-source command-line tool like Ghostscript to substitute generic fallback fonts. Install Ghostscript on your machine.
There is no official .ttf or .otf file named "F1" or "F2". Cid Font F1 F2 F3 F4 F5 Free Download
If you know the person who sent you the file, ask them to send it again with the correct settings. Tell them to export the PDF using the option in their software. This packages the font data directly inside the file so it displays perfectly on any computer. If you only have the broken PDF file,
If you created the document and others cannot read it, you must re-export it with embedded fonts. Open the original document (Word, InDesign, etc.). Click or Export to PDF. In the PDF settings, look for Optimization or Options . Ensure Embed All Fonts or Subset Fonts is checked. Save the new file. Method 4: Use a Different PDF Engine If you know the person who sent you
-> tab) to see what the actual font was supposed to be (e.g., Arial, Times New Roman).
Many F-series CID fonts are part of the Adobe Acrobat Asian Font Pack . If you are seeing errors with F1 or F2, downloading the official Adobe Font Pack often solves the issue instantly for free.
These are internal aliases (nicknames) assigned by the PDF generator.