HTMLDOC Problem:

Htmldoc produced no pdf-output.
Commandline:
/usr/bin/htmldoc --bodyfont Helvetica --logoimage fileadmin/synapsy_com/synapsy-logo.jpg -t pdf13 --linkstyle plain --no-links --webpage -f /srv/www/synapsy.com/typo3temp/hd_4KcxYv - 2>/srv/www/synapsy.com/typo3temp/se_i47mv5

This is the (stderr) output of the htmldoc command without the htmldoc_append parameters:
If you see no errors here please check your htmldoc_append parameters too.
sh: /usr/bin/htmldoc: Datei oder Verzeichnis nicht gefunden