While preparing the camera ready version of a paper, I had to upload the paper to IEEE PDF eXpress for validation. The validation service threw the following error at me
Font Helvetica, Helvetica-Bold, ZapfDingbats is not embedded (300x on pages 2-4).
There was, to me, no obvious way to fix it and their online documentation proved not helpful either. I tried a few avenues, but in the end I settled on a solution using Ghostscript. This was the only one that properly solved the issue and (seems to have) left the rest of the document intact. I found the solution I ended up using via Stack Overflow and provide it here. The Ghostscript command to use is
gs -q -dNOPAUSE -dBATCH -dPDFSETTINGS=/prepress -sDEVICE=pdfwrite -sOutputFile=output.pdf input.pdf
I will admit to not having delved in what each option means as I was getting
annoyed with the process. This should however automatically see which fonts are
missing and embed them in the resulting PDF file. Note that you may need to use
-sFONTPATH option if the fonts are not available in a standard location.
See 1 and