How to fix unembedded fonts in a PDF
Embed every font so the RIP renders your text, not a substitute.
Check which fonts are not embedded
In Acrobat, File → Properties → Fonts lists each font and whether it is Embedded or Embedded Subset. Anything without that tag will be substituted at the RIP.
Enable font embedding on export
In InDesign/Illustrator, export to PDF/X (Press Quality) — it embeds fonts by default. In Word, File → Options → Save → "Embed fonts in the file".
Replace fonts that block embedding
Some licenses forbid embedding. Swap those for an embeddable equivalent, or outline the text to vector paths as a last resort (you lose live text).
Prefer full or subset embedding
Subset embedding includes only the glyphs you use — smaller files, fully safe for print. Full embedding is fine too.
Verify before you ship
Preflight flags every non-embedded font with a page reference, so a substitution never surprises you at the press.
FAQ
What happens if a font is not embedded?
The RIP substitutes the nearest font it has. Character widths change, text can reflow, and unusual glyphs may render as boxes or drop entirely.
Is subset embedding safe for print?
Yes. A subset includes exactly the glyphs used in the document, which is fully sufficient for print and keeps the file smaller.