AFAIK that is legal thing with Adobe, not technical, where they won't let you edit font in PDF unless you have that font active on the system.
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Except the poster was not speaking of editing fonts in a PDF.
He mentioned "Illustrator" was complaining about missing fonts.
Re-open an Illustrator file (.ai - .eps - .pdf) without the fonts loaded
and it does not care if you told the fonts to embed in the previous save.
MSD
