Welcome to the forum.
Wrong workflow. The RH project that created the CHM can
produce other outputs. What you do is create a printed output as
described in the Printed Documentation article on my site. Don't be
put off by the length of the article. Producing the output is
simple but the article explains pretty much everything in detail.
In theory you can output direct to PDF but most people find
there are some tweaks they want to make in Word first, better page
breaks and so on. You can also create the PDF from Word.
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