Many times the title question is sent to ML. Hope my experience would help you.
Check Start with 4 steps.
1.Installed jodconverter and swftools? NO -> see install instruction
2.It works? How to chk: >cd /<your jodconverter path>/jodoconverter
>java -jar lib/jodconverter.jar /<some input test file>.txt /<some output test file>.pdf
the pdf file is not created -> see your error message and fix it
is created -> jdconverter works
3.Swftools works? How to chk: >pdf2swf -help
appear error messages -> fix them
appear help list
FINAL:Check your OM configuration
login with admin -> Administration -> Configuration -> jod.path & swftools_path need to match with the real path